http://www.snapfiles.com/get/browz3d.html

Real quick and easy one. Freeware.
You add and delete folders (just navigate a selector window to the folders you want to browse).
no textures, of course, but verts only, wireframe, or polygons (transparent or opaque).
You can zoom or rotate models, and sort the model list couple different ways.
That's it; but it's really fast (should be at or close to real time)
Occasionally it gets confused and really mangles the view; but it's normally pretty good.

I know it works with .obj, .dxf, and .3ds
Some others are listed (including .lwo) but I don't have any those to try it out. I'm guessing it will work; because I've never had any problems with it.

Friends don't let friends use booleans.