Surprisingly DDO is a really good P2P game but came out a couple of days after WoW, in which WoW just tidal waved over it.
Right now its going F2P/P2P/Cashshop. But the Cash shop points are easy to get without actually buying them.
Also its combat is actually different than generic mmos. And class can be customized up the butt. I mean you could be a knife throwing priest for all i care.
Just look at all the cool things.
www.ddo.com
In my personal opinion DDO is The BEST MMO ive played so far, (that includes WoW, Aion, CoX, AoC, FFXI, Any Free MMO)