Sure, you could wear a Safe Turn indicator for night rides, but why lift your arm when the Spooklight has a wireless handlebar touchpad. Its accelerometer also shines your brake light when you slow down—just like a car.
The LEDs are super bright, and a built-in lithium polymer battery keeps them juiced for about 60 hours. At that point the Spooklight comes off the bike and charges via USB. And this is pretty cool: it will also charge your gadgets (like MP3 players and cellphones) while you're on the road.
£55 ($88) is on the pricey side, given you can still just wave your arm to change lanes, but if you ride about at night quite often, it could be a good investment in your own safety. Either way, points for the clever use of the three-axis accelerometer. [50Cycles via Wired]