For a long time I've been dumbfounded regarding bike lights. Most of them don't have any kind of comparable information apart from the price, and for us who live in countries that actually get dark, the light might be _the_ most important safety device there is.
So, I did what every mad commuter would do: Went to the shop to buy lights, put them on a faux-handlebar (ie. a pitchfork) and took photos of the light patterns for comparison.
You can find my blog post about it here: http://bit.ly/bikelights
I also tried to categorize the bike lights in order to truly compare them irregardless of their price. I would be awesome to have an independent party to investigate the bike lights similarly like car safety is tested, and to have some kind of unified scoring on different lights as most riders can't test them out in real environments before purchase.
Thoughts and comments on the categorization would be highly appreciated! What other values as brightness and light pattern should we take into consideration?