Make your own 3D printing filament from recycled bottles and other plastic products. Never run out of 3D printing filament.
Filabot is a 3D plastic extrusion system. For example mostly any type of recyclable plastic... kickstarter
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A Desktop Machine To Turn Your Old Plastic Into 3-D Printing Fodderfastcoexist.com
Filabot Turns Your Plastic Junk Into Material for 3-D Printers