I don't remember all of the stupid people on here; Kitty's covered the main ones. I do remember a troll called zebra1, who used to post about enemas and peeing all the time. She popped up last year, posted a post about peeing which I promptly removed, and hasn't been seen since.
There was also back when we had guest posting a spate of guest trolls posting this incredibly obscene photo all over forums; one poster made this thread that was pretty much just the obscene photo posted dozens of times. -.- It basically was a man pulling on his poopy hole; I'm not going to name it as I don't want to be responsible for people googling it out of curiosity then being totally grossed out.
Boss Hog; one of postgreps fanboys; he wanted to become a mod and supported postgrep in his quest to become one. There was also this user called purplefoxx that was fairly innocuous up to a point, then megaspammed the forums. Not in a rude or obscene way, but she basically replied to every single thread in Comments & Suggestions showing she too had ambitions for modship.
In fact, there have been literally dozens of people who have asked to become mods; either directly, by PMing the mods, or indirectly by doing what purplefoxx did.
Fairybabe should NEVER have been made a mod; she was absolutely awful. -.- Not only did she do what Kitty said, she also told off one user, DrkTenai, so nastily that DrkTenai sadly left the site and never came back.
Fairybabe also used to post her photo everywhere and say that she was ugly just to get attention; she also closed any thread that she personally disagreed with.
The "Is 10 Too Young?" thread.
Basically, there were at least five fights within it, all by 10-13 year olds who felt themselves mature to date so decided to prove it by being extremely immature, attacking people who disagreed with them, and flaming the mods.
One such person was bens_cutie, who registered another account to back herself up. The irony was that her and the other children who started and participated in the fights could not see that what they were doing was not helping their case one bit.
There was certainly more than one, and every one ended with a mod locking it; whether cuz the mod themselves cough*fairybabe and LilAngelEyes*cough* disagreed with abortion, or as a result of a full on flame war. None of these people ever seemed to learn from this, and most of them were pro-lifers and/or the under 13s, who had never been in the situation so really couldn't judge anyone who had. This is why whenever we see an abortion thread on here, we know its days are numbered. O_o
"OMG! I'm pregnant!!11!eleventy!"
We used to have loads of these threads popping up in General Discussion and Dating, and they were mostly posted by people who'd only just joined. There were also quite a few people claiming to be teenage mums, but most of them told lies so were quite obviously just attention seekers.
One such person claimed to have lost her virginity at age 12 (her name was Hollister Hottie or something similar) and had a baby girl; however, she posted another time that she had a baby BOY. She could not keep track of her lies at all, and when called on them went all emo and posted a thread entitled "I'm going to commit suicide!"
Erin (little_sister_smile) and myself came right down on her for that one; I will point out that back then, I was not a mod. XD She also had the same in her sig; she removed it after being told exactly how stupid she was and how attention seeking was not going to be put up with on here.
Maybe I'll add more later; if anything comes to mind.