Heres two that could have made it on the list:
1. In Doug Marshalls last fight were he ran and jumped clean out of the cage and started running around in the audience.
2. I doubt anyone has seen, but in an old IFC event, this guy William Knorr, after winning his fight, attempted to show off his acrobatic and karate skills, and failed miserably. He got up from the ground, where he'd won the fight, then promptly lay back down for no reason, and tried to do a kip-up. He was in his 40's though and couldn't actually do one, so he got up and almost hit the ref in the face with a molassas slow spinning cresent kick, and then started doing some kind of kata. Keep in mind this guy is the definition of a karate redneck.
Honorable mention: When a shirtless Joe Son and Kimo ran into the octagon after Royce Gracie threw in the towel before fighting Harold Howard, and told everyone that God had struck down Royce Gracie. Then BJM told them to get the **** out of the ring.