Wrong Way Nut (Mk2)

Two nuts travel opposite directions on the same thread! As seen on YouTube! http://www.youtube.com/watch?v=o-fPsvqjqZI

Update 27 Oct 2011: I've uploaded a new trick nut triplescrew_backward_floor.stl which eliminates superfluous slack and reduces the overhangs to where they might be buildable on a Makerbot.

The YouTube video inspired Thingiverse user msruggles to design his own "Screwy Screw" thing. The STL files below are the originals, which were used to make the video, which inspired