Fancy an evening at the cinema? Just start pedalling, mate

In the depths of Notting Hill, 20 pairs of trendy feet are poised on pedals.

Their owners have arrived on bikes which have been lined up in front of a huge projector and hooked to a generator, which for the next 90 minutes is going to power a free cycle-in cinema. If one bike stops, the film does too - disappointing the 100 cinema-goers who have gathered behind them in a converted warehouse under the Westway.

"Get set, go!" There's a whirring of wheels and, to everyone's relief, A Town Called Panic begins to play.

Adam Walker, 30, of green energy organisation The Magnificent Revolution, says: "We wanted to create Fifties-style drive-in cinema, but powered by bikes. We've done it on a smaller scale, but it was a lot of work. With 20 bikes everyone should be able to pedal gently."

The event is showcasing the versatility of bike-powered generators, which cost about £30 to make, and there is even a free smoothie stand, which is powered by customers, who arrive on cycles that are hooked up to the blender's blades.

The silhouetted cyclists need to create 900W, but if their staying power wanes they can raise their hand (or beer can, in some cases) to signal for a replacement from the audience - who are listening to the film using wind-up portable radios.

"It's a great idea - it's good for the environment and gives you a workout," says cyclist Laura Goldney, 23. "Plus you don't have to worry about where to leave your bike, like at a normal cinema."

With their relaxed bring-your-own booze, picnic-style atmosphere, pop-up cycle cinemas have been a hit all over the capital this summer, from a screening of experimental film Kino at the Open City London Documentary Festival, to classic cycling flick Belleville Rendez-vous at the Herne Hill Velodrome in Brixton.

But the two-wheeled phenomenon has not been limited to cinema.

At cycle cafés, such as Clerkenwell's Look Mum No Hands, Lock 7 in Hackney and Micycle in Islington, visitors can lunch while their bike is fixed. And at design store Do in Covent Garden customers are actively encouraged to bring their bikes inside.

"We love bikes and want our customers to spend time here without worrying theirs will be stolen," says shop assistant Fernando Gonzalez.

This summer of cycling has spread beyond the functional to the fantastical: in June, 1,000 Londoners rode naked through the capital for charity, while Pedibus, the eight-seater cycle with a bar, has become an overnight hit. Perhaps the climax of this craze will be the screening later this month of Dutch group Bike Smut's rather unusual production Bike Porn, a film that pays homage to the sexy side of cycling.

Mike Cavnett, a spokesman for the London Cycling Campaign, says: "Cycling has doubled in the past 10 years, so people are catering for the ever-growing army of cyclists. When London gets hold of a cultural phenomenon, there's no stopping it."