An impressive list of weird keyboards can be found here. My favorite is definitely this one (patent here), it's crazy!!!

An ergonomic, efficient unitary pyramidal-shaped data entry device includes left and right hand members separated from each other by a thumb control surface. Each hand member is formed with four cavities for receiving the four fingers of the left and right hands, respectively, of a user, with the user's thumbs being juxtaposed with the thumb control surface. Each cavity contains three switches, with one switch being operated when the user extends the appropriate finger, a second being operated when the user depresses the finger, and a third being operated when the user retracts the finger. Each switch generates a signal representative of a character of a character set, with thumb switches being operable by the user's thumbs to invoke one of a plurality of sets. The sets include a character set that mimics the conventional QWERTY layout, and also include sets which represent language-optimized layouts. The device can also assume the function of a telephone and a cursor control pad.