First thing I'll say, is despite the claims, I was really impressed with how bright these things are. They're powerful, especially for their size.
Because of how small they are, I've taken to carrying mine[1] in my pocket. Mostly, it was for amusement value. These things are a lot of fun to play with. However, you also never know when you'll need a flashlight.
Well, tonight it happened. I was walking into the bathroom, went to turn on the light, and nothing happened. When the light is out in the bathroom, it is pitch black in there, and I wasn't amused (I had to go rather badly;-). Then I remember my flashlight, pulled it out, and life was good.
These things seem a little expensive at first (Almost $20 each), but trust me, they're worth it. The battery life on them is really impressive, they look cool, and they're essentially indestructable. They even come with a lifetime guarantee. If they stop working for any reason other than dead battery, the manufacturer will replace them free of charge.
They also make, I've discovered, great geek gifts. ;-)
If anyone is considering getting one of these, this is a good page to check out, specifically their photographs of each color being displayed.
Now if they'd only come out with a violet one. ;-)
If you're wondering, yes, I think these things are really freakin' cool. ;-)
[1] I purchased a red and a green Photon II light. I got the red, even though it's less bright than most of the others, becuase of the 120 hour (that's 5 full days) of use battery life, and because it doesn't disturb night vision, making it useful in the car and hiking, when you want to keep good visibility. I got the green because I like green, and it supposedly has a longer battery life than the other 'bright' colors. I'm considering getting a blue and/or turquoise soon, too. ;-)