I legitimately enjoyed Priest. I think it's because growing up, vampires were really the only movie monsters that actually scared me, and then popular culture when and made them fantasies for teens with stuff like Twilight, Vampire Diaries and True Blood (I think). Priest was the first movie I'd seen in a while to portray vampires in a manner that a normal teen-aged girl wouldn't want to wrap her legs around. I actually didn't realize it was considered a 'bad' movie until a few months after it came out. I kind of avoid reviews for movies I really want to see, so my enthusiasm doesn't get ruined. My friend rather rudely burst my bubble about it one day, but I still enjoy it.
But a 'so bad, it's good,' movie? I actually don't really know. Nothing jumps to the top of my mind. I liked Van Helsing. A lot of people tell me that it wasn't that great, either, but I don't really think it's in the realm of 'so bad, it's good.' I'll have to mull this one over a little bit more.