Re-Revised 3x2x1 Rubik's Cube

This is nearly identical to my prior version http://www.thingiverse.com/thing:3485 . It's been slightly altered so that instead of totally hollow external cubes the interior sides come up to a point - so that there is a minimum 45 degree angle support for the top part. The next version I upload will have totally solid cubes with additional improvements discussed in this blog post http://makerblock.com/2010/08/revising-the-3x2x1-rubiks-cube/

All parts are contained within a single STL. Make