Well, here are the most commonly played free ones:
Realm of the Mad God is free to play, and is available on Steam.
World of Warcraft (Generic response, I know) is also free up to level 20.
AdventureQuest isn't that great, but it's free.
Runescape used to be a huge thing, but it isn't that great anymore. Still free though.
Vindictus is one of the best free-to-play MMORPGs out there, in my opinion. It's built off the source engine, so if you plan on playing it, make sure your computer can handle it well.
Discussions
7 years ago
Well, here are the most commonly played free ones:
Realm of the Mad God is free to play, and is available on Steam.
World of Warcraft (Generic response, I know) is also free up to level 20.
AdventureQuest isn't that great, but it's free.
Runescape used to be a huge thing, but it isn't that great anymore. Still free though.
Vindictus is one of the best free-to-play MMORPGs out there, in my opinion. It's built off the source engine, so if you plan on playing it, make sure your computer can handle it well.
Have fun!~