Any mmorpg

Runescape?

If you're looking for free / no download, look here:

I would recommend EpicDuel, it's a brand new PvP MMORPG with no download or installation. You can play for free at EpicDuel - Free MMORPG for your web-browser | No downloads. No installation. Play for free!

Go to pawngame.com click on a link that's called pawn tactics, its not 3D because you look at the screen from a birds eye view.

Fighting MMORPG:
Runescape,Sherwood dungeon.

No-fighting games:
Switch in,OurWorld (I can't remember whether it's 2D or 3D sorry.).

Afew sites with MMORPG lists(Some required downloading but it will say in the description):
List of MMORPG 1
List 2

Old topic but it is still worth adding a few games here:

If you are looking for browser based games that you don't need to download anything.

1 - Drakensang - Read Drakensang review here>
2- Call of Gods - Read Call of Gods review here>

For future reference you can check out Free MMORPG online games list