Found this one while looking around for more Halloween inspired hacks.  Hari picked up a bunch of rubber rats at the dollar store and decided to make a Halloween project out of it.

A Raspberry Pi connected to a Pi Cobbler breakout board, and a 16 channel i2c PWM servo controller puppet an array of rubber rats.  Everything is powered by a pair of hobby LiPo batteries and 5v regulators.   The rats eyes were swapped out for some bright red LED’s giving a pretty authentic haunted house look.

There’s still time to put something like this together before Halloween!