The Nintendo Wii, hands down!
It's just... reveloutionary. It's cheap, compact, has really wacky games (In a good way) and has INTERNET AND AN EMULATOR eek
The emulator in question, you have to pay with Wii points, but still, it's a emulator for NES, SNES, TurbographX16, some sega games and the N64! (Zelda Ocarina of time!)
Anyways, it's Nintendo Wii FTW!