The riots after Maskaev-Rahman
The Fan Man incident in Bowe-Holyfield II
Tyson-Holyfield II The Ear Bite
Tyson-Savarese when Tyson kept swinging after the bell
Gatti-Gamanche one of the sickest KO's ever, you thought Joey was dead

And a personal one for me, RJJ vs Art Serwano when Roy hit him so hard I thought Serwano turned into a zombie...his face looked like the face of the people that gal from The Ring killed.