[FierceDeityLink]

There's a lot more materials in Half-Life 2 than the ones you named, but I don't remember ever seeing one for rubber/springs (although ropes could work a little like them).

Personally, I don't like the physics engine in Counter-Strike: Source. You can't barricade halls just by pushing objects (you have to frag grenade them into place). I don't like running around and accidentally running into a bucket and being pushed back. Barrels are equally useless. Tables, cabinets, etc. break the same way every time, but the wood in chateau causes massive slowdown when it explodes (by frag grenade). I'm hoping that all of these problems won't be in Half-Life 2, and that most are probably caused by synchronization pains regarding the net-code.