I currently have a NES, SNES, N64, Gamecube, Playstation, Playstation 2, XBox, XBox 360, Gameboy SP, and PC.
In the past I have owned all the various models of the gameboy and a Sega Genesis. I also used to have a DS but I left it on an airplane.
I suppose eventually I will buy a PS3, if enough cool games ever come out for it.