This text file is the repo of sites for files for 3D printing:

Free / Open Source / NC Use / GPL / Attribution:
thingiverse.com
myminifactory.com
youmagine.com
3d.si.edu
3dprint.nih.gov
grabcad.com (via free registration)
traceparts.com (via free registration)
shapeways.com


Free & Paid:
cults3d.com
stlhive.com
makersmuse.com


Paid: