Keypad Kit
Brian writes –

we’ve produced a set of kits to create monome-like devices: a logic kit (the important part, includes pre-flashed atmel chip and all parts, 100% through-hole soldering = easy to assemble) and a keypad kit (includes pcb and our custom keypads). all source files, parts lists, firmware, schematics, and layouts are posted for your better understanding and custom projects. devices made with these kits can take advantage of our continually-growing library of open-source user-contributed software.

monome – Link.