For those of you who are still disappointed by the fact that the iPad can only run the iPhone OS; this one is for you.
According to TUAW, the folks over at KamaGames managed to run nothing less than Microsoft's Windows 95 on the iPad via an emulator. It's slow as hell, but it multitasks and features Minesweeper. Isn't that what you were asking for?
Anyway, nice achievement. Check it out (youtube link):