Wikipad has announced a MFi version of their controller for the iPad mini called the Gamevice. The full spec controller has dual analog sticks, a d-pad, and eight buttons spread between two pieces that surround the ends of the iPad mini. On the pre-release model I saw the halves were connected together by a thick elastic band that allowed the controller halves to easily hold on to the iPad mini.
Price or release details haven’t been announced yet, but Wikipad is targeting a release before the holiday shopping season. It looks like an interesting addition to the ever expanding range of MFi controllers. Now, if more developers would just add support for them! You can sign up at the Gamevice site to get more info on the controller.