I just spotted this on one of the gaming websites I read -- this guy has modified his Silvia with a PID, a 20-character display, and a microcontroller, with an NES (original Nintendo) gamepad for input! Theres even some cold cathode lights in there for some extra bling:

http://growdown.blogspot.com/2006/11/custom-silvia-pid-mod.html

Definitely worth checking out, even if just for the "wtf" factor