Trapazoidal Cube Generator

Generates a hollow trapazoidal cube. I am using it to generate custom matte boxes for small cameras.
UPDATE: Much thanks to Synchron (http://www.thingiverse.com/Synchron/designs) for helping me simplify and improve my original silly script. This does what it's supposed to do, now.
UPDATE 2: Trapezoids have been made available as of OpenSCAD 2014.03, see fluidity's comment