10. Lt. John Pike
Yes he can look super-lackadaisical while burning the eyeballs out of people for loitering, but that doesn't mean he'll make for a chill dinner guest. If you thought your Uncle Rick was a reactionary when you suggested that maybe hypothetically Obama wasn't a remote-controlled robot invented by the Kenyan Socialist Party, wait until John Pike comes in to watch the game and decides you've been hogging the recliner too long.
9. Herman Cain
There's a good chance one of your other guests is presently suing him for sexual harassment. If not, there's a good chance they will be by the time dinner's over. Even if you keep him away from all the women at the table, there's no telling what he'll do to the food. Dude is horny!
8. Rioting Penn State Kids
Fact is that college kids are just as stupid as high school kids, except high schools are good enough to discourage their students' expression while colleges encourage it (UC Davis excluded). If any of these kids shows up at your table, prepare for some really poorly thought-out diatribes about the injustice done to "Joe Pa." We certainly did some regrettable stuff in college, but what ever happened to spending a semester or two as bi-curious vegan with a minor in Kabuki Theater?