Over 38,000 open-source designs for 3D printers have been uploaded to Thingiverse.com

"MakerBot also supports Thingiverse.com, where users upload their open source designs. There are designs for over 38,000 items, including jewelry, iPhone cases, and lens cap holders, but also a Virgin Mary toast press, a Mario mask, an alligator head, duct flanges, battery trays, and Advent calendar puzzle pieces (a toy — like an X-Wing starfighter, a snowman, or a mini MakerBot Replicator — within each piece)."

Source:  The Magazine, 14th March 2013