Felfil is a new open source filament extruder from Italy. It will enable you to recreate it in your home workshop and produce filament from pellets.
Felfil homepage:
http://felfil.com/?lang=en
Extruder details and downloads:
http://felfil.com/felfil/
Improved version of FelFil, the FelFil Evo is on Kickstarter:
https://www.kickstarter.com/projects/948513712/felfil-evo-a-filament-extruder-for-3d-printers-mad
Here is video of it: