Gameknot

Yes, and it's decent enough. Has all the basics - blitz games, rapid games, 2-day per move games and up to 14-days per move games. There's a variety of tournaments, and other areas then such as rated tactics, daily puzzles, openings DBs, post-game computer analysis. It's free up to a certain level (think it's 12 games max at any one time)

Interface is very clean and easy to use, I find. Typically 1,000 people online at any given time - small by the standards of, say, chess.com, but enough that you'll always have a game.

Blitz games are unrated, which I've heard others say is annoying, and there's nothing on endings (chesstempo has endings training, for example)

But if you want something for basic casual play, it's perfectly fine.