My parents were clearing out their loft when they found an old Lego Technic 8860 car that I had as a kid in the 80s. I built it with the help of my kids (much fun) and brought it to life with some motors and a Raspberry Pi. Check out my blog for more information:
http://pdwhomeautomation.blogspot.com/2012/11/raspberry-pi-powered-lego-car.html
Cheers
Paul