Here's a thought after looking at the OP advice. In addition to ignoring trolling, start and post to non-trolling threads!
Or you could always do like another forum I was a member of did.
Create a "Garbage can" and "Soap box" section or sections and move crap like cary's "Americans have little dicks" threads there if you're not going to delete them! They would even move an individuals posts there if he or she was doing nothing but trolling in that particular thread!
Thanks for bumping this up with another good suggestion!
Expect announcements on forum changes a little later in the day....
Trolling is being deliberately annoying to bug people and get a reaction. Imo, that's what you do. I doubt I'm the only one who views you that way. Btw, you said you were leaving, so why are you still here?