Parametric Drywall wall Anchor

I needed some anchors to attach a http://www.thingiverse.com/thing:1830 to my wall.
Rather than take a 10 minute trip to the hardware store, I spent 45 minutes designing and printing some. They worked pretty well.
There are parameters to adjust for different size screws. The parameters are currently set up for a #6 drywall screw.