- Twilight Struggle
- Hive
- Patchwork
Choosing one really depends on mood. Twilight Struggle is the kind of game you have to buckle up and commit to playing for a while, but it's worth it. Hive and Patchwork are more bite-sized - both have enough complexity to be interesting, but with a much lower time commitment. You also have to refer to the rulebook less often with those two games. :)
Interestingly, it's written by Aaron Griffin - the former Arch Linux lead dev.