Triceratops

This is a Triceratops scan from artec3d.com's gallery. I reduced the mesh from the original and converted the file to STL.

This model requires supports, but the support marks aren't too much of a problem since they're out of sight on the underside and the skin texture also hides them.

I kept the mesh resolution high enough that you should be able to scale this even larger with good results. The size of this model is about 7 inches long by 3 inches high, and I estimate that my Replicator 2 could print it up to 50% larger.