QuattroBox. Fully 3D-printed MMU system with interchangeable extruders (with or without gear reduction), filament eject buttons, status LEDs, and spool enclosure. Modular and open-source.
QuattroSync.
Batalhoti-Doron-Velta. Modifications I made to my Doron Velta
DumpTube.
Bata-0.
