First of all, the iE3 is the quintessential keychain flashlight ... turn it on and then twist it back to turn it off. This handy light has just one mode – 90 lumens – and can throw about ...

[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 ...