I’ve played before.
If you like Jeopardy, and you like bars and bar crowds, you should like Bar Trivia.
It is MUCH more fun to play with a group of people that you know and like. I have played with my own social friends, and with my co-workers, and while I like my co-workers, the vibe is much looser and happier with my friends. I cannot imagine playing a pickup game with total strangers, but I am a solid introvert and can only work up the energy to play once a month or so, so I’m a bad one to ask about that.
The specific rules differ with different bars. What seems to be pretty constant is that there is an emcee who announces or passes out the questions, that cell-phone use is strongly discouraged (but done anyway) and the questions come in rounds or categories with different topics or areas of knowledge.
There are often a range of prizes, usually ones that have to be fulfilled at the bar (so the bar makes money regardless) So for example, you could win a round of drinks for your team if you get a perfect score on a single round, or you could win a shared appetizer or bucket-o-beer or a limited bar-tab for winning the whole night.
People can get really into it, and lots of places have standing teams that play regularly. Some teams are all about winning, and are very competitive, some teams are just about being there, and may never win, but are there for every single week.
The fun of it is to balance the fulcrum between smart and drunk, so you’re loose enough to make wild connections and enjoy the contest, but not so drunk that you forget everything or get too wrapped up in the competition.
Like Shagnasty said, it goes much better if you have a sort of United Nations approach with your team and their varied interests. Even if not, you can still have fun.