Here's another one: argumentum ad servitus, or "appeal to slavery." This is when someone denounces a society, philosophy, policy, or economic theory by comparing it to slavery. Of course, if the person makes a legitimate comparison, it's not a fallacy; the fallacy comes from comparing something to slavery in order to make appeal to ridicule or poisoning the well fallacy. Since it covers these and several other fallacies as well, I think it should be considered one of its own.
It's kind of similar to Godwin's Law, so maybe the person who makes the comparison should be considered to have lost the argument.