My list is so unimpressive compared to the others here. I sold my NES, Sega Genesis & CD, and SNES a couple of years ago, leaving the communal systems:
PlayStation2
Nintendo GameCube w/ with Gameboy Player
and my handheld collection:
Atomic Purple Gameboy Color
Milky Pink Gameboy Advance (imported from Japan)
Platinum Gameboy Advance SP
Platinum Nintendo DS "Phat"
White Nintendo DS