Now that the iPad has sold over a million units, there are plenty of folks out there wanting to make the most out of their expensive doodad. One of the ways you can do this is to jailbreak your iPad, which will allow it to run unofficial apps. I'm not going to recommend jailbreaking, since there is somewhat of a risk, and you do void your warranty, but if you are the gambling sort, behold some of the things you can pull off.
Having an SNES emulator on a jailbroken handheld device isn't news, but when an iPad is jailbroken, it allows you to link the Bluetooth to just about any Bluetooth-capable device. In this case, you can link your iPad up to an ordinary Wii remote.
It's not ideal for playing "Super Mario World" (not enough buttons, after all), but there are plenty of Bluetooth controllers that would work fine here. Now, toss a stand on your iPad and you suddenly have an incredibly capable (albeit quasi-illegal) classic gaming hub on the go.