Spotted on the Make: Flickr Pool, a ATTiny45-based USB device that takes control (as currently programmed) of the target computer’s Caps Lock key, switching it on/off at 30-second-to-8-minute intervals (and flashing the Caps Lock light in the process). Fully programmable to do other desktop shenanigans (e.g. random key presses, cursor movement, etc).

Stealth USB CapsLocker