Dumb people who think they are smart

[Blarg]

Yeah, for those subjects having a sense of humor and good stories are usually better than being particularly smart.

Sports is an especially good one to bring everybody in, but works better with guys than girls. Even guys with zero in common can have a great yap about sports though, and you get a new subject almost every day. Plus you can be real competitive, needle and put down each other's teams and manhood without anyone taking it seriously.