This is my personal adventure into the world of Global Illuminaton, complete with hand-made OBJ/MTL loaders.
Its current stage is "Massive WIP" and comes with no suggestions that it
will even slightly work for anyone else or on any machine other than my
own.
At this point, any information provided in or by the files should be
taken as unreliable reference works and should not be used in any
situation, production or otherwise.
For a good selection of .obj files, try Morgan McGuire's Mesh Page.