Wired: Save 100 yen, shoot some aliens.
In this thrifty age, Japan has come up with some pretty cool piggy banks, some of which Brian Ashcraft wrote up for Wired magazine last year. I think this Space Invaders bank beats them all, though. It's a 1:6 scale replica of the original sit-down Space Invaders machine that was all the rage in Japan back in the day, and you start the game up by inserting a 100 yen coin. The controls - not to scale, of course - are on the side of the unit.