joystickbutton for your r0ket
Every attendee of the Chaos Communication Camp 2011 get a r0ket-badge. It is possible to enhance the 5-way-switch to get a better look an feel by using a 3D-printer to manufacture a nipple-mouse for it.
Here a some pictures of the r0ket with and without the printed cap.
You can get the .STL at thingiverse.com and print your own: