I try to take note when I see a useful program in hopes that I can find it when the need actually arises. I use Proteus ARES for my PCB and schematic and it has a cool 3D Viewer for the final PCB. Authoring the objects is a different animal than just using the pre-existing 3D objects but the image mapped objects seem pretty sparse.
Check out the list of 660 file formats that they convert at: 660 File formats for 3D Conversion