Want to play classics like Mario Kart and Chrono Trigger on the iPad? Given Apple's closed app ecosystem—and the relatively undefined legality of using console game ROMS—the procedure involves a little jailbreaking. And you'll also have to shell out cash to play, paying $6 to download snes4iphone or SNESHD from the Cydia marketplace.
Once you jump through these hoops though, you'll be taking advantage of the tablet's generous pixel real estate in no time. Video instructions below:
Obviously you can apply the same step-by-step to your iPhone or iPod touch, so long as your device can be jailbroken to run Cydia. Full text instructions are here.