ATtiny85 TV-B-Gone

A keychain remote that turns off (almost) any TV in range. Mitch Altman's classic prank, rebuilt on a 50-cent microcontroller.

Difficulty: Through-hole. Estimated build time: about 60 minutes. Estimated parts cost: about US$3.80. 10-part bill of materials with live supplier pricing. A pocket-sized universal off-only TV remote.