By "tessellated" I only actually mean that for polyhedra that appear to do so when looking into them, with the insides of the faces being mirrors.
I think this reply is the first because people don't understand what you mean by:
"Are there any interactive visualizations of arbitrary tessellated polyhedra?"
All I'm seeing is big words that make no sense (not that they don't make sense). 
Yeah, sorry. Sometimes I say things a little too technical for most people to understand.
"Tessellate" means to tile a shape in 3D.
"Polyhedra" are the 3D equivalent of polygons.
Does that help you understand it?
Do You think of
Username=dan garcia&ProjectName=Platonic Solids 3D
Username=trg078&ProjectName=obj loader
Although not particularly interactive, it seems like a good place to start.
Like the first one but tiled.
Yeah. I already knew what tessellated means.
As for polyhedron--like a 20-sided die?
Dice are polyhedra, yes. In this case, a d20 is an icosahedron.