I know a browser based game is a far cry from other games, but being a casual gamer I liked Ikariam for a little while. It is interesting, but does not have a good theme to keep it interesting.
Actually I find the game to be quite good to play for relaxing after a rough day, although it does have some pretty high wait times for building and recruiting, I love the graphics, they are so bright and attractive, overall I think it is a brilliant game.