You already know that GitHub is pretty awesome for hosting your source files, but how about your 3D object STL files ? Awhile back they added a 3D file viewer to give you live previews of your 3D objects. Now they’ve added the capability to see the differences between revisions.
When you compare 2 versions, one object is in green, one is red. Then there is a slider to let you transition between the old version and the new version. This method of comparing 3D models is much better than doing a side by side comparison, as sometimes the difference is so slight.