Matt Hope is a British artist living in Beijing, and in response to the terrible pollution of the city of more than a million bicycles, has come up with the 'breathing bike' – an invention that creates clean air for the rider to breathe as they pedal.

Beijing's air quality, which almost ruined the Olympic Games there, often becomes so bad as to threaten public health – wich puts people off cycling despite it being one way in which emissions could be reduced.

Matt's invention is carbon-neutral, using a pedal-powered generator to power the home-made air filter.

Filtered air circulates through a hose that's hooked up to a fighter pilot mask.

But it's not quite ready to go into production yet: Hope says: "If you ride this in the rain, you could potentially kill yourself."