How much do you spend on securing your bike?

£0 I live in the Vaucluse (think Ventoux), and quite happily leave my expensive carbon framed bike outside local cafes. Why would I drag around the weight of a bike lock?

For me it's based on risk of the bike being nicked and how much I'm prepared to tolerate.  For my utility/commuting bike that I'd leave in a city centre, station etc (all day) it's a silver grade D lock (£30) through the seat stays, a secondary cable lock through the frame/front wheel (£30), a thin wire strop (£10) from the saddle through the helmet vents (onto D lock) and a cafe combo lock (£10) for very short stops, or if the bike is in sight.  I also have a pinhead wheel lock on the front wheel in case I haven't got a strong point to secure the wheel to.  It's a pretty old bike, but has some good (upgraded) components on it so I'd rather not have the nausea of having to replace it.

For the road bike (which I wouldn't risk in the same way as the utility bike) it's just a cafe lock (£10) and I have occasionally squeezed a mini D lock (£40) between the seat pack and saddle if I'm perhaps leaving it out of sight in a higher risk area.

My utility bike locking routine does attract some odd looks but, having read some of the other comments here, I'm with like-minded people!

Couple of other things.

On a couple of my bikes, it's possible to lock the rear quick releases with the right size padlock round that and the chain stay/hole in the drop-out, in such a way that you can't slide the padlock off either end of the lever.

Also, if I need to lock the mountain bike up, I run a lock through the suspension fork brace, as well as through the frame and wheels - otherwise, it's surprisingly easy to steal £500+ of forks, if you don't have security skewers.

I employ a full-time manservant to ride with me (a respectful distance behind me, of course) and then stand guard over my bike whenever I leave it anywhere.

This is going to be a very controversal answer for many of you.  Before I get into my next shocking statement there is a qualifier to my answer, and that the locks I'm talking about are ones that you can comfortably carry with you, not some 17 pound chain wrapped around your waist, but something less than 7 pounds.  

I personally don't believe any lock, no matter the amount of money you spend will, in todays world, stand up against a professional attack by a very determined thief for more than a minute and half!

I've read many reports of locks getting the Gold rating only later to find out that they were easily defeated.  So why even bother spending a fortune for a lock only to go to your bike to find it gone?  Sure the more expensive one may slow down the attacker by 30 seconds but that's about it.  The real cheap locks will take about 15 seconds to defeat so there is that to think about, but I think a decent midgrade lock is all that is effective to last around a minute.  All a lock in todays world will do is stop the opportunist.  

Why spend say $5,000 for a 14 pound carbon fiber bike only to riding with a 17 pound lock?  That just doesn't make sense to me to be carrying around a lock heavier than the bike, not only that but the extra weight of the lock defeats the purpose of having a light weight bike.

The other issue with bikes is that if you have a bike with top of the line components, a thief could simply strip parts of the bike, though in todays world it would take longer to do that then it would be to steal the bike anyways.

Also the bike protection insurance that some locks offer you aren't worth the paper they're written on.  You have to jump through a lot of hoops that most people won't and can't do and thus never get any money for the bike.  These loops I've found are in the American versions of the best locks, not sure if these same loops apply to other countries.  Here in the States you have to have the following at the time of purchasing the lock to be sent in to the Kryptonite:

Contact details
Lock information including a copy of the itemized receipt of purchase
Key number of your lock
Vehicle information including vehicle type (bike/powersport), base cost, the serial #
An itemized copy of the bill of sale
An image of your bicycle or powersport vehicle

Then at the time of theft you have to this:

Report the theft to the police within 72 hours.
Immediately report the theft to your insurance company, if covered by insurance.
Notify Kryptonite within seven (7) days of the theft: submit a ticket through our website

Contact details, including your email address.
Registration confirmation number, (would be in your registration confirmation email).
Copy of the official police report.  (this one is a huge problem in big cities because police departments won't waste their time doing police reports for stolen bikes)
Description of the lock-up - provide info on how the lock failed (we always recommend locking to a secured stationary object). (They will require pictures with the description)
Image of the broken lock*.
Image of one original key.
Proof of deductible from insurance company, if covered by insurance.

*Kryptonite reserves the right to request the actual lock...and they will want the defeated lock, if the thief took the lock there will be no coverage.

 Of course you have to buy the registration program and pay the fee for up to 5 years (you can pay for shorter terms but you can only renewal it once for a total not to exceed 5 years), after the 5 years expires you have to buy a new lock and start all over.  About 99% of all bikes that are stolen when a Kryptonite lock was being used the owners never saw any money, but they would get a brand new lock!  Krptonite ran into a lot of flack over their warranty by a large network news program about 5 or so years ago and they have sinced streamed lined it as detailed above, but  I haven't heard is what percentage of bikes they are paying claims out for now, my understanding that they are paying about one to two percentages more than they were before, but this is information that the lock company would not share with the news story and they won't share it now, but the news story was able to get a close idea due to complaints they received after a bike was stolen.  They seem to be a tiny bit more willing to pay the deductible for your private insurance but they are not so willing to pay for the bike itself, so it behoves you to have private insurance.  

If you have a really nice bike and are fearful of having it get stolen then there is a way to prevent that from happening...don't ride the bike and leave it someplace where that could happen, instead if you need to leave the bike unattended you could buy a decent second hand bike for around $400, buy a decent lock for around $45, and save the nice one for rides where you know you won't be leaving it unattended.

All I use for a lock is a Abus Disc lock and a cable that I've used now for about 35 years, but I don't park my bikes in high crime or even medium crime areas, and always highly visible and within my eyesight as well.  All my places I've ever worked at they let me bring the bike into my office so there was no need to lock it up outside in a large city area where I worked.  I was lucky in that respect.

No name, no stated purpose therefore no input.

Outside - zero. I simply wouldn't leave either of my bikes unattended and hate carrying a lock strong enough to keep them safe(r)

All the budget has been spent at home - ground anchor, secure shed, etc. But ultimately I didn't need to do that either as my house insurance fully covers me for theft. The only reason I bothered is because the bikes are self-builds and as such have a certain sentimental value. Both low-run frames that are no longer available so they're effectively irreplaceable. 

Online: No ride sharing on social media, big Strava privacy zone

When I used to commute (on my best bike) I never locked it at work in 3+ years of doing so, I guess I was fortunate in that we had very secure bike parking - unless there was an inside job. 

With every new bike I also buy new locks.

Ranging from a 400g Hiplok over a 1,2kg Hiplok lite, a 1,7kg Trelock TORO FS 500 up to a 3kg Abus Granit CityChain X-Plus 1060. Additionally I have some smaller locks - chains, folding  and u-locks, cables, an alarm Target TL050 and an alarm disk rotor lock. All in all I guess I spent over 500€ on locks so far.

I usually do not leave my bikes unattended for longer periods. Most of our bikes are in my cellar and locked with everything I got. When I am out on my bike I choose the matching lock for the activity. If I do not plan to leave my bike unattended, I choose the 400g cable Hiplok, so in I can leave it whithin visual range for when I buy a coffee or something. If I have to let it outside of a doctors office for an hour or so, I will have at least two of the heavier locks and the disk rotor alarm lock with me. I wouldn't let my bikes stand outside for more then a few hours in any case.

For bike touring I will take both the Hiploks and the alarm lock  with me and still make sure, that the bike will be inside a da shed or something over night.

£300-something eight year old hybrid; locked up with a £65 Kryptonite New York mini (the Fahgeddaboutit); pentagonal security skewers on seatpost and wheels.

At home I have 

1x Hiplok Gold bike lock £80

1x Hiplok Airlock - £100

It's rarely unattended, for coffee stops I carry a small deterrent Hiplok Z-Lok.

You might see a trend here, Hiplok are a small local, UK company who make great specific products, it makes me happy to support them.

Nothing as I don't leave it unattended and my Brompton comes with me into places. 

I've just spent £95 on a new lock and chain for use in the shed/workshop. I just loop all the bikes together at the moment, as they'll need to cut the chain to get the bikes out the obstacle course and through the door anyway, so a ground anchor wouldn't really add much to the security.

In the van, as the van is alarmed, I just use my old u-lock and cable to lock through a channel in the van. The cable is just to slow them, so if they do get in the van, it's not a quick grab and go, which I'm hoping would be enough to scare them off.

At home I have an Asgard shed, £450.

Then out and about I have a gold rated D-lock, £24, and a cable lock that the D-lock goes through to secure my child seat, £12. Have a reasonably secure shed at work so don't go crazy on locks.

Pay £220/year to insure my two bikes (worth £1500 & £1100 new), so if they get nicked then not that big a deal. Already had the bike I had sentimental attachment to stolen, so the current two being stolen just means new bike time.

A few hundred thousand as my bikes stay locked in my flat and do not ever get left when I'm out & about.

Each bike I have has the following for out and about:
Gold Sold Secure D Lock ~ £30
Security Skewers ~ £10
Cafe Lock ~ £10
Braided Cable ~ £10

In my last place I had upgraded my shed security for the three bikes that lived in there with:
Security Screws ~ £15
4x Butterfly Stands ~ £15 each
1x Wall mount bike hanger ~£5
3x Wall Anchors ~ £10 each
5x Keyed Alike Disc Padlock ~ £10 each
1x Disc Padlock Hasp & Staple ~ £15
4x Hardened Steel Security Chain ~ £10 each

Having had the misfortune to snap a key off in the external padlock and one of the internal padlocks (learnt my lesson on regular oiling now) I know that it is not easy getting through this security. The shed was broken into once (back when I used a combination padlock on the external) but they did not take anything inside as I assume it was too much hassle for what the bikes are worth.

At home, I have ground anchors in the garage and use motorbike locks through them - my best bike has 2 going through separate anchors. Hopefully, it'll slow the bastards down enough to be caught in the act.

There are 2 bikes generally left un-locked - the commuter bike is old and in need of work, so I wouldn't mind so much if it went and the other would be fairly easy to replace. I'm hoping any thieves that get in will just take them as easy pickings and leave the rest alone.

When out on the pub/shopper/errand bike, I use a Kryptonite U-lock, backed up with a cable through the wheels if I'm leaving it for any length of time. The skewers are anti-theft - I've come back to a bike once when left at a station to find all the bikes in the rack had had the QRs removed and variously thrown in the bushes/on the tracks.

I keep a motorbike lock in the bike shed at work for the commuter bike.

I once had a bike stolen from a station rack - Kryptonite cable cut with bolt cutters. Couldn't believe anyone would steal that heap, but at least I got the padlock back!

At home, non bike specific perimeter security for areas such as garages and sheds. Ground anchors are a good investment. But if a thief targets high value bicycles then once they have gained access and if they are willing to make noise then no reasonable security will stand up to an angle grinder.

Rule of thumb, each £10 spent on a lock will gain you 5 seconds of protection against a tooled up thief.

Unfortunately the simple solution is not to leave any bicycle in a public area that you would be too distressed to loose. My daily hack has sentimental value only. I use a £10 lock when I do have to leave it outside Tesco simply to prevent someone just jumping on and cycling off.

Spending a lot of money on a lock for an expensive bike simply means you stand to lose an expensive bike and an expensive lock.

On my road bike:  not a dime as I won't contemplate leaving it parked by itself for even a second.  Besides:  all locks except some heavy ones are crap and those that work (somewhat, nothing resists an angle grinder for longer than a minute) are heavy and unwieldy.  When I take it to the office it stays in the room with me and at home it sleeps in my living room.

On the bike that I use for shopping (costs about 2k EURO new) I spent 100 EUR on an Abus 'U' lock (granit 54plus or something).  I leave it attached only for the time it takes me to purchase groceries.

I live in Brussels, you'd have to be crazy to leave a somewhat valualbel bike outside, even attached.  If they don't manage to break the lock or steal components then they'll smash up the bike out of spite.  Police are a joke where bike theft is concerned, they simply don't take it seriously.

At least 10-20% of the value of the bike.

A good lock will last for years, and then become the accessory lock/leave at work as you buy bigger to deter the latest level of scrote.

Security skewers are great.  I'm going to splurge on HexLox for the new build.  And am considering a Pragamasis 16mm chain for a leave at work lock.