3D model marketplace MyMiniFactory addressed the recent issue with shady eBay sellers pulling thousands of 3D models from Thingiverse and reselling them in violation of the creators creative commons licenses. They also launched a new feature on MMF that allows users to add a label, or signature to their model automatically when it is uploaded. The system will discretely add the creator's username and a short link to the item on MyMiniFactory when the model is verified as printable. The user only has to check a box and MMF will take care of adding the label. You can find out more about this new feature over on 3DPrint.com: http://3dprint.com/121759/mmf-new-auto-labelling/