A combination of safety light and camera, the Fly6 watches the backs of cyclists  

The Age has an article on an interesting crowd funded invention for recording badly behaved motorists from the rear of a bike - A combination of safety light and camera, the Fly6 watches the backs of cyclists.

A slingshot projectile in the bum, followed by frustration about the idiocy of some road users, inspired two Australian entrepreneurs to invent a device that will watch the backs of vulnerable cyclists on the road.

Called the Fly6, it is a combination video camera and flashing rear light that promises to make riders more visible while recording what happens behind them. It is fitted to the bike's seat post.

The inventors say it could also help to determine who is responsible when a motor vehicle hits a bicycle from behind – one of the most common causes of serious injury or death among cyclists. ...

The inspiration was at first to make "people who do stupid things like that" more accountable, but they soon felt it could have a preventive effect. "If motorists just thought there was a camera potentially on a bike, they would take it easy and we’d have a much better time on the road," says Hagen. The Fly6 has a camera lens in the centre of the flashing bulb cluster on what looks like a standard cycling safety light. It records at 720 x 1280 definition, with a 130-degree field of view, while capturing 30 frames per second. The device is waterproof and also records audio. Recharged by USB, its lithium-ion battery runs for more than five hours.

It comes with an 8GB class-10 microSD card, which holds some two hours of footage. The camera automatically overwrites old files on a loop, so riders don't need to delete old video.

In an accident, a switch inside the unit shuts the camera down if it lies at an angle of 40 degrees for more than four seconds – which prevents the crash data from being overwritten. For the weight-conscious sports cyclist, it tips the scales at just over 100 grams.

In recent years, cyclists – and motorists – have been using video cameras to record their road movements, to use for legal or insurance purposes in the case of an accident. Attempts to determine responsibility often boil down to the driver’s word against the cyclist – if the cyclist wasn’t killed.