ilves: I'm usually not one for the casual online games that you play once a day, but I actually found one through a friend that I enjoy called Estiah.
www.Estiah.com
It's kind of like an RPG that you play, each day you get a certain amount of action points with which you can do dungeons, fight other players, etc. There are also different classes and stats you can advance in, giving you different abilities (called charms in the game). It's fairly simple, but there's a lot of advanced strategy later on in building your 'gear' for combat, especially if you're playing against other players as you don't know what their builds are going to be. If you like those sort of games I'd recommend giving it a look. If you do play, tag me as your 'mentor' when you sign up, my character is under the same name, it'll give me points in a skill.