Blu-Ray laser keychain

http://hackadaycom.files.wordpress.c...ray-laser1.jpg

[Jay] hacked a Blu-Ray laser diode into a keychain enclosure. He found a heavy brass keychain light from Lowe’s and stuffed the diode and a larger battery inside. The existing batteries weren’t powerful enough, so he drilled out the endcap to fit a 200mAh 3.6v lithium battery inside. He also modded the power button to only momentarily turn on the diode. With the larger battery, the laser can run for about an hour between charges. In addition to a Blu-Ray lasers, he also has versions with a 200mW red diode.

http://hackaday.com/2009/06/25/blu-ray-laser-keychain/

Sadly, despite the cool factor, this is a Darwin award waiting to happen. I hope anyone who tries to imitate him is very careful about reflections with this thing. You can permanently scar your retina with something like that - quite literally - faster than you can blink. Apparently he knows laser safety, at least.