I reported pedonigger spam a few times a long while back. Otherwise I have really only reported threads that were obviously posted in the wrong forum requesting they be moved.
I've never reported shit on here, I also haven't been here that long though, but if someone were spamming I probably would report them, for that or of course if they were suspected of being no good backwards dastardly commie bastards snooping around this fine neighborhood.
Sometimes I will tag a staff member to witness somebody being a retard and weigh up their triangle status, but unless it was like CP spam, I wouldn't bother.