Settlers of Catan is fun- resource gathering and building roads. There's an Xbox Live version of it as well that is very well done.

Ticket to Ride I think I like even better than Settlers, if only because Settlers is a bit too much of a slave to the dice. In it, you build lines of train cars between cities, and try to compete for longest routes.


(Those two were also both on Tabletop, I believe)

Chrononauts is cool- it's a card based game in which you manipulate the timeline to your liking. At the beginning of the game, you're given a character and a mission. To win the game, you either have to
1) Change the timeline so it matches the one your character is from,
2)Acquire the rare objects for your mission, or
3) Repair enough paradoxes that you are invited to join the Time Police.

You do this by flipping events, like saving Abraham Lincoln from being assassinated, which can have ripple effects further up the timestream. It's kind of hard to explain in writing, but it's pretty easy to learn.