Why, it shows how many times you've been cured or cursed!
It really doesn't mean anything, but technically some people may curse you if you do something particularly funny, good, while you would get cured if you do something particularly rude or nasty. But like I said, it won't change anything about the boards for you. You can also get them by doing special things around the boards. The floating heads or...Nathan's trousers come to mind.
Hope I explained that well enough.
