I have some .max files as modder's resources i'd like to use in the future. How would I go about using them?

with 3ds max. likely nothing else will open them.

depending whats in them, you might be able to cohearse someone to export the contents. if no one chimes in on here, I guess making a req thread might help

Oh. I thought they were just files you drop in the Meshes folder or something. So it's kind of like a .zip file, where the stuff has to be extracted?

Not quite extracted, but rather exported. they are complex 3d scenes. specifically for 3dsmax. they could, in theory, contain anything that you can do in max. ie mesh/spline objects, particle systems forces and deflectors everywhere, cameras, animation keys for like anything, materials, rigs/bipeds with mad crazy complex scripted controllers wired to the guys ass... you get the picture.

Basically the raw form the assets would be created in by many game developers. from there they would export to a format the game engine will consume. here it would be nifs and kfs.