There's wakfu if you want to try. Its quite a bit different from any other mmo out there (with the exception of dofus, its older brother created by the same company) in that its combat is tactical, as in Final Fantasy Tactics and etc. A while ago bay12 had a guild in it and all, but people eventualy just ended up leaving. Thus far, the game is still undergoing some significant changes, class wise, and they just added a new class. I still play it on and off, but I might play more often if some bay12 people want to team up with new characters.
Its on steam now, too, and completely free other then cosmetic items, exclusive mounts, pets and sidekicks (which are special characters that you can control alongside your actual character). You can buy things like experience boosts on the shop too, I think, but the game isn't grindy untill higher levels, and even then only if you're going solo and not with a group of people due to how the xp distribution works. Professions, however, can be grindy to level.
Game is in its late beta development stage, and classes are still being adjusted, but its quite a complete game by now. They just did a change to how character stats are organized and and etc, so its not entirely newbie friendly, meaning you'll prob want to read a guide or two about a certain class if you want to play past the early game. Its reasonably easy to reroll your character though. New content is constantly being added.