Portal USB Desk Defender: 2010 - ThinkGeek
This was one of the most complicated projects I've undertaken at ThinkGeek. The project required us to convert a digital character into a real, 'working' toy, but the character wasn't quite designed to exist in the real world. It's got spindly legs and a mechanism that seems to exist in an alternate dimension. The end result is pretty nice, but I wish I could have left in a battery compartment for hardware hackers. The product's only functions are to detect motion and then say a catch-phrase from a list of in-game quotes and to vibrate and 'die' when knocked over.
Portal 2 Sentry Turret USB Desk Defender $39.99