I found this these new rubber button from sparkfun through the make blog. They even say that they where inspired by the monome in creating them.. (I'm sure the people at monome are loving this). Though they haven't yet got the boards that work with them on sale yet.. making them pretty worth less until they do. Once they do I'll probably buy enough of these parts to create another magic box. The size of which I haven't yet figured out, maybe just a small 4x4, for switching between sample sets in my live patch. But another part of me wants to have a back up for the box or maybe even a 128 button box. That would be nice, 128 buttons, but the rubber alone would cost me something 160 dollars... . I'll just wait and see how much the boards will cost from spark before I come to a conculsion. The backend will once again be from ucapps.
Here is a little chat I had about this on the em411