Online Multiplayer Games - Interstate?

My sister and I live in different states and meet up at least once a week to play Literati (Scrabble) online. Are there any other good games out there we could play together that are free ? We have played games in Yahoo ! and Games.com, but I am sure there are lots of others out there that we are unaware of. We used to love Rock n Roll Jeopardy, but they took that off.