This is the PianoArc, an invention by Brockett Parsons. He's a keyboardist for Lady Gaga, so he wants an instrument as outlandish as his boss. With 294 keys, it's 3 conventional keyboards put together. The exterior diameter is about 6 feet. The height is adjustable and the PianoArc can be set at an angle.
Now hopefully people will take me seriously when I talk about my idea for a circular set of bagpipes.