These look cool
http://wiki.protoneer.co.nz/Raspberry_Pi_CNC

Pair with a touchscreen lcd and you have an all in one solution for a desktop mill.

Not worth it for me though as I have a spare dell laptop which has a flip touchscreen to work as a pseudo tablet which should be ideal to build into the machine and gives me a much bigger screen to work on and a very neat solution and if I do need the proper keyboard and I flip it back round.