Minimalistic spool mount

This is my mounting system for my minimalistic spool ( http://www.thingiverse.com/thing:8331 ), but it should work with most other spools with a bearing center, like "Simple spool system for a Mendel (or other 3d printer)" by brokentoaster ( http://www.thingiverse.com/thing:3962 ) and its derivatives, and "Another spool" by CCphoto ( http://www.thingiverse.com/thing:8208 ). It mounts to the back of a Cupcake and has a filament guide to lift the filament up and feed it down into the extruder.