This challenge comes from ideas from this thread
Idea & Brain storming "adjustable size CNC" 1'x1' to 3'x3'
http://www.element14.com/community/thread/21466
A portable CNC wood router that straps onto a 4x8 plywood sheet (maybe ratcheting nylon straps), uses an umbilical to attach to a "dock" that provides power for x, y and plunge axis and holds the laptop. Capable of cutting 2d shapes, not sure of what spec for the thickness of plywood.
Have at it!