If you are getting a bunch of guys together to play a board game, you may as well make it a nerdy one. Battlestar Gallactica (BSG) is the board game version of the recent TV show of the same name, and is the best game tie-ins that I have ever seen in terms of capturing the flavor of the original work. This has a downside; of the 5 players we had, one was unfamiliar with the show and was initially quite lost as to what was going on.
On the show, humanity has been all but destroyed by surprise attacks on the 12 colony planets by killer robots (the cylons), some of which look human. Luckily a small fraction of the population happened to be aboard various space craft at the time of the attack. Unluckily, it was the whiniest and most depressing fraction but on the plus side they managed to get away with the one remaining military vessel and a bunch of smaller craft. Now they travel the galaxy in this ragtag fleet looking for a shining planet known as Earth and arguing with their fathers. The cylon fleet (which is much cooler) is hot on their trail and if that wasn't bad enough the humans have been infiltrated by human-looking cylons that cannot be detected. Some of the traitors don't even know they aren't human until they are activated!
A basic episode of BSG has the fleet jumping out of hyperspace into an empty region of space. They can only jump so far before stopping to a while to chart a new course. Some sort of problem will occur (an explosion, or plague, or a riot) that everyone will argue about for a few minutes. Then suddenly the cylons will appear and start hammering away at the fleet. The only choice is to jump back into hyperspace as soon as possible, but that means leaving some of the slower ships behind; hundreds of people will be killed. Then something else happens to delay the jump - is it bad luck or is it one of the traitors? There is a reason nobody is smiling on the box art work.
The board game plays out exactly like the show, each player plays one of the main characters. At the start of your turn you draw a number of "skill" cards from different decks as determined by your character, the president draws lots of politics cards but no piloting cards, etc, etc. The board is a representation of Galactica and surrounding space - a turn consists of moving your piece to a location and taking some action determined by your cards or the location. For instance, you can play an engineering card to repair any location you are in, or in the Admirals Office you can try to force another player into the brig without playing a card.
At the end of your turn you draw a crisis card - this usually shows some horrible event that is about to befall you. Sometimes this involves cylon ships appearing around Galactica, but often it is some sort of on-board emergency like all the water escaping into space. Now all the players have to work together to resolve it by playing any amount of cards from their hands face down into a stack. One crisis might require lots of engineering skills to resolve, so the engineering characters are expected to play lots of cards, the other characters may not be able to contribute much. Also, 2 random cards are added to the stack as well just to shake things up. Once everyone has played, the cards are shuffled then turned over and their values added up. Cards with the appropriate skills add to the total, those with other skills reduce it. Failing a crisis by not meeting the value printed on the crisis card causes bad stuff to happen - usually some critical resource is reduced.
Of course, the players are all supposed to be working together. But true to the show, some of the players are possibly cylons and are acting against everyone else. Because of the way crisis card are resolved, they do not have to reveal themselves in order to sabotage humanity's chances. Anyone suspected of being a cylon can be put in the brig, which limits the damage (or assistance) that player can do - but of course there is nothing to stop false accusations. And sometimes particular characters may want a crisis to end if different ways for other reasons, so a canny cylon can do a lot of damage before being found out. This is not a game you play to win friends. 
The game we played ended with the cylons winning with the humans nowhere near earth. Partly this was due to some bad decisions the humans made early on when we were not quite familiar with how to get anywhere, but the original cylon really messed with us before revealing himself (revealed cylons stay in the game, and can do all manner of cruel things). I ended up being a cylon halfway through the game, and managed to get the best human pilot consigned to the brig while cylon raiders attacked with impunity. BSG offers that rarest of delights - the ability to screw somebody over with them having no knowledge of what is happening!
The game play is fairly fast once you get going, but be warned - BSG is a long game. We took about 4 hours to play but I think you could easily play in less than 3 if you knew what you were doing right from the start. Although there is quite a lot of stuff to do in a turn, the mechanics are easy to learn and play proceeds quickly. There is not a lot of downtime, even on other peoples turns you will be called to provide assistance to resolve the crisis card. And accusing other players of sabotage is a occupation that never gets old.
Highly recommended if you like the show, recommended anyway if you haven't.