Pix Sports (Multi Functional Sports Light ) - £11.99 delivered from BlahDVD.com (48% off)
Go through Quidco for 5% cashback.
The extremely trendy PIX Sports is a watch, stopwatch, stepometer, night signal, scrolling text message display and motion response display. All this and you can wear it around your neck or clip it to your clothing with the supplied clip. It's even showerproof.
As well as its gym-based uses the PIX Sports is a brilliant visibility tool. Clip it to your sleeve or the back of your bike and you'll be flashing as you're dashing and pulsating as you're pedalling. That's because the PIX Sports features a motion sensor which causes the LEDs to contract and expand across the screen. In signal mode the PIX Sports will display several animations, including a solid bar of all 75 LEDs, a large arrow and various other patterns formed by the blinking lights.