The Master Curvy Copter is an edge-turning cube with two layers on each turning axis. I first presented this puzzle back in August 2010, and I have redesigned the mechanism several times since then. This mechanism is very stable, and rarely locks up.
You can order stickers from Oliver Nagy here: http://oliverstickers.com/stickers-for-shapeways-puzzles/eitan-cher
You will need twelve 4-40 5/8" or M3 16mm flat-head screws.