Prusa i3 compact extruder

Not created by me but by sgraber, adapted from a design by Kliment.
Best way to get it is from the source: https://github.com/sgraber/i3ext
But some people asked me to provide a simple printable version so here it is.
You can see it working: http://www.youtube.com/watch?v=fu9SWw5dcGk