The Interactive LED Coffee Table, designed by Because We Can and Evil Mad Scientist Laboratories, is a coffee table with LEDs that is interactive. They are motion sensitive, and light up as you pass objects over them. When they don't detect motion anymore, the blinking slowly fades. You can purchase one for $1,990, or get a do-it-yourself kit starting at $350. I'm so glad these are available, because let's face it -- a coffee table just isn't a coffee table until it gives you a seizure.
Product Site [thanks to the very bright HelenKate for the tip]