Example of skeleton setup for a game engine
This character with skeleton and with all controllers (included sneak-walk animation, keyframe)
(for Maya 4.0. or higher, with Maya 5 controllers work are not correct)
This skeleton has a minimum quantity of joints, because it's very important for a game engine, each vertex has not more than two matrix. Keep in mind, i made this skeleton setup approximately two years ago, many things was changed, but something not.