Atari 2600, NES, Master System, Genesis, SNES, Game Boy, Saturn, PlayStation, N64, Wii
Unfortunately my Xbox stopped working a while back, or else it would be on this list too. Also, while I do play the 2600 every now and again, the Genesis gets the most time out of all of these, including the Wii (well, until this Tuesday, but I've even been taking that slow, and am just now up to Mr.Sandman).