I can never have too many projects... Printed out the ' Finger Starter ' for InMoov , an Open Source articulated humanoid robot (well... the upper half anyways). Printed in polycarbonate (PC) with a carbon fiber fill. Instructions call for drilling out inner holes with 3.5mm drill and outer ones with 3.2mm drill, but I currently don't own any metric drill bits. I found the 5/32 for outer holes and 1/8 for inner holes work perfectly for using 3mm filament as a joint pin. It took about 2.5 hours to print and another half hour to find the parts and wire it up.