our 3D printers are now such high resolution we need higher resolution 3D models so we don't see the facets when we print.
Take a Stanford Bunny. Decimate It. Subdivide It. Repeat. Repeat. Export to STL.
You should have almost all the detail but almost none of the visible 3D model facets in your print.
NOTE the before and after screenshots from Blender where you can see how the 3D model improved.
UPDATE 2011-09-18: I uploaded the FLATFOOT versions which should skein a bit easier. choose high res or super high res if you really want to make a big print.