iCade 8-bitty is your iOS device's new wireless NES controller
The device, shipping "later this year" exclusively from ThinkGeek for $25, is compatible with the same lineup of games the as the iCade cabinet, and includes a d-pad, start, select, and (an anachronism we'll learn to deal with) four buttons. It's also got handsome faux woodgrain accents.
As with the bigger iCade, there's an open-source SDK, so any app developers out there can add support to their apps and make this thing all the more appealing.