So check out this forum post from a [H]ardOCP reader (lowrider007) who owns a Ageia PhysX card. It seems that the "Cell Factor" game which is supposed to not run at all without a Ageia PhysX card can run just fine without it.
Install the demo, install the latest physx drivers from their site and add EnablePhysX=false to the CF shortcut and voila, no physx hardware but fully playable game and most importantly full physics
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