It's been a while now, but a group of seven of us would very occasionally set aside an entire Saturday to play Diplomacy. While online and play by mail have their own flavors, the tension and negotiation strategies while face to face have a character unlike any other board game I've played.
Between sets of moves, groups of people would scatter to different corners of the house for hushed discussions, and unlike online play, you could make a decision based on who you saw talking to whom. With a large board on a dining room table, it felt like being in a war room with all of Europe at stake.
All in all, it is an extremely compelling game with strategy in both moves and alliances leaking from all seams.
Between sets of moves, groups of people would scatter to different corners of the house for hushed discussions, and unlike online play, you could make a decision based on who you saw talking to whom. With a large board on a dining room table, it felt like being in a war room with all of Europe at stake.
All in all, it is an extremely compelling game with strategy in both moves and alliances leaking from all seams.
[0] http://www.diplomacy-archive.com/resources/strategy.htm