A variation on the Mendel extruder, using a reprap-printed gear drive.
From: http://vimeo.com/10269267 . Original Description: This is (yet another!) design for a geared extruder for the RepRap Mendel machine working. This one is intended to mount directly in the machine, or to mount to one side and drive a Bowden extruder, or to mount to one side and drive a Bowden paste extruder.