I posted up about these lights in another thread a while back, but this time, I've bought them and installed them.
I got my set from a seller on Ebay - but they're imported locally by SCV http://www.scvimports.com.au/products.p ... d=&id=6435
These lights mount to the axle bolt with magnets mounted on the spokes and they light up as you ride due to the passing magnet causing induction currents. A common criticism is that since their mounted so low this might interfere with visibility/effectiveness - but I'm not convinced. They wont light your way, but then again, they're not meant to.
They're designed to fit instantly on modern bikes, but with a little rejigging I fitted them to my commuter, a circa 1990's steel framed 12 speed roadie.
The front light pretty much went on as designed but the rear didn't because of the RD mounting. I had to mount rear light on the pack rack stay which resulted in a non ideal magnet sweep meaning the rear didn't get maximum current, but it still lit up and blinked less brightly, however being higher up might make it more visible.
These are the power back up model, which means they stay blinking for a minute or two while stopped, eg. at traffic lights. (the rear currently lasts 5 seconds though due to non ideal magnet sweep
I wasn't exactly happy with the rear situation, so I dropped a line to Reelight and they mumbo'd to the party in no time flat. Awesome. It's not their fault the mounting bracket didn't fit properly on my bike, but they didn't want their product operating lees than ideal so they're sending me some additional magnets (more magnets partially inducing current should provide enough current) and also sending a possible solution for the axle. How's that for service!
Since we seem to love stats at BV forums, here's a ripper: according to their customer service manager, they have a study that shows that bikes fitted with Reelights have 32% less collisions than bikes without. Now this is in the Danish context, but it seems to make sense directionally since anything that helps you be seen means a better chance of being avoided.
Anyway, I'm pleased. Having them means I always have a blinking light of some kind when I commute.