Fiasco is a very well-designed game for a cooperative story-telling experience that gives you the feel of a Coen Brothers movie or any of hundreds of other movies where people with powerful ambitions and poor impulse control hurtle through the story on train tracks greased to hell. Winning is having a blast helping these sorry characters try to fulfill their dreams and watching things go gonzo and fall apart spectacularly.
The game is simple in process (easily learned in one demo game of a couple hours). There is such great reception and fan support that fans have been writing "playsets" for the game like crazy. There are tons of them out there for free as the Bully Puplit Games guys fully encourage folks to make them and ask that they be given a chance to look them over and help make them better.
The best games occur when participants embrace the strongly "improv" style of the game. It is optimized for 4 characters, one of which can also be the "facilitator" to help newbies with the process, but are also full players. No GM required. It's the perfect pocket game when you want to fill a few hours at a con or try something different with your home crew.
If you can let go of the character sheet and enumerated powers and strengths, jump in and have a blast making a Fiasco!