Printing separated parts that can fit

Please refer to http://www.thingiverse.com/thing:52946 instead. That is a better solution. (2013-02-27)

Printing separated parts that couldn't fit has always been a problem to me. I tweaked the skeinforge engine in ReplicatorG to add an offsetting 3D model inward funtionality. Here is the result http://www.youtube.com/watch?v=ieMXp1h0iM0 .