If you want something that is guaranteed to liven up the party, the Shot Glass Roulette is it. It brings everyone together because once you take it out and start a game, people will naturally gravitate towards it.
It is fun for an adult gathering and will definitely gives you a lot to be jovial about. The more people play, the more they drink and the more lively the party will be. Just remember to know when to stop when things get a little high!