I think when you know the whole story 'Pat Smith vs. Scott Morris' is probably one of the scariest. According to Big John who reffed this fight when he was on Eddie Bravos pod cast he detailed that in this fight the Referee could not stop the fight, he simply was not allowed to no matter how bad someone was being beaten.
He said in the POD cast that he explained to the corner men (who at the time were the only people other than the fighter able to stop the fight) that if he thought the fighter was in trouble he would say 'Check your fighter' and that if he thought the fighter had had enough we would say 'Watch your fighter' (it might be the other way around but it is similar to that).
Anyway as Pat is beating the shit out of Scott Morris big John is screaming at his corner 'Watch your fighter' over and over. Apparently out of the view of the camera the corner man actually turned around and threw the towel into the crowd. Essentially forfeiting any way they could actually stop the fight, it would be later explained to Big John the Scott actually instructed his corner that under no circumstances were they to throw in the towel.
Meanwhile Pat is landing some of the nastiest elbows we have ever seen in the UFC and it was only his compassion for Scott that he actually stopped and got off him without Referee, Towel or Tap out stoppage. This could have EASILY been a death in the UFC and there was no one really in a position to do anything about it.
If you want to hear the story (and many other really cool old school UFC stories) go on Youtube and search 'Eddie Bravo Big John Pod Cast'.
I cant embed but in case anyone needs a refresher here is the Vid.
http://youtu.be/aVSpZZHBupA