From the Physx site:

Quote:

How do I become a licensed developer and what are the licensing terms?
Costs
At present, the following two options are all that are available. We will likely never provide any sort of royalty-based license. Open-source usage is limited only to the most middleware-friendly license model--in other words, we retain full ownership and rights to our own IP, and what you ship of ours will still be specified by contract.

Free:
Non-commercial use
PS3 platform (through Sony pre-purchase)
Through some of our middleware partnerships, such as UE3, Gamebryo 2.2, and others--often limited to non-commercial use
PC platform (if the game makes significant use of PhysX HW)
$50k per platform:
All other uses
Fee may be waived at our disgression for multi-platform developers providing PC HW support
Fee may be waived at our disgression for some Tools & Middleware providers