Porn Star Jenna Jameson Is Now Even HARDER

TMZ has learned that porn princess Jenna Jameson picked up a new ride for her collection yesterday ... if you call a Rolls Royce Phantom a car. Yes, Jenna is riding in something.

The white 2007 Rolls Royce Phantom, which costs more than some houses, set Miss Jameson back about $360,000. TMZ spoke to Jameson, who told us, "It's the ultimate car and I can barely see over the dash (laughter) ... and the Ogara Coach Company took great care of me." Who doesn't?