I hear GuildWars is popular and a very good game with a strong focus on PvP. It's not free but fairly cheap. If you buy a package, no monthly fee.
http://www.guildwars.com/products/guildwars/
Also, there is a game called Mythos; not sure if this is MMO or MO. A bunch of developers of Diablo II quit Blizzard and have been making this title. In this sense, this is Diablo III. It's in a beta stage now.
This is basically a free game, but you pay for items if you want. But you can also get those items without paying if you complete quests etc.
MYTHOS Screenshots:
ALPHA Build
BETA Build
Mythos Trailer
http://file.4gamer.net/movie/mythos.zip
Gameplay footage
http://dungeonrun.com/2007/07/26/mythos-beta-gameplay-video/
Official Site
http://www.mythos.com/
Unofficial Site
http://mythos.incgamers.com/
A lot of screenshots and movies
http://hellgate.incgamers.com/gallery/showgallery.php?cat=526
No, it's not going to stop 'Til you wise up
No, it's not going to stop So just ... give up
- Aimee Mann
