This is one of my controllers for live computer music. It is actually two Apple Magic Trackpads I used some grant money to purchase a time ago and realized only recently the value of such multitouch interfaces. What I have done here is construct a nice tray that holds them a fixed distant apart, disables their click, and has a non-slip bottom that restricts the potential for movement during the piece.
The tray is made from ABS and Polycarbonate plastic. It has a nice little 3D printed logo on it, made extra grimy by a few coats of paint that have worn away. It was too clean anyway, too much apple smoothness and plastic wears on the eyes, gotta have some grime somewhere.
I largely use these in correspondence with “fingerpinger,” a Max external capable of breaking out the HID data from OSX. I also have a port of this external to Pure Data, kindly supplied by Tom Erbe. The original code that both of these are based on can be found here. Either way, these are used to pump out OSC messages to my DAW or DSP code of choice.