[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 ...

There’s a whole lot of interesting mechanics, optics, and electronics inside a Blu-ray drive, and [scanlime] a.k.a. [Micah Scott] thinks those bits can be reused for some interesting project.