You have more than 42 half finished trucks on your lawn for decoration! Oh, wait, that's rednecks.
But no, really. If you own any Geforce 8xxx, 9xxx, or 2xx series video card, Nvidia released new drivers that enable the CUDA processor system onboard, and gives you a full Agiea Physx card on your video card. What this means in the short term? Not a whole heck of alot because most games don't support PhysX. yet. That was mostly because there were very few PhysX cards. Now there are many, so you should start seeing more mainstream games employing it. Especially since it is easy to implement. Nvidia.com for the updated driver, they have some neat demos there too.