1. The Exorcism of Anneliese Michel
The woman that inspired both films The Exorcism of Emily Rose and Requiem, Michel's possession tale is a sad one. After years of convulsions and strange actions, there came reports of her stripping off her clothes and drinking her own urine.
Michel decided that all of these incidents were tied to a demonic possession. She refused to eat or drink anything because the demons wouldn't allow it (which also helps explain the horrible transformation in the video below). Father Arnold Renz and Pastor Ernst Alt were given the order by the Bishop of Wurzburgwith to perform an exorcism on Anneliese Michel.
During the exorcisms, which lasted for months, it was revealed that Michel had 6 demons living inside of her. 40 tapes were recorded of the ordeal. Michel, however, died at the age of 23, due to malnutrition and dehydration. She would also lose the ability to walk and break all of her front teeth from "biting the corners of the walls in her home and the furniture."
Her case was later ruled to be not a possession, but that hasn't stopped the movies and gruesome distribution of tapes like this:
2. Demon Chair
This video came from an evangelical website - disregard the links and check out this demon-strapping chair. Forget the fact that this scene seems to have inspired the entire Constantine film; that chair is freaky. And so is this track-suited demon girl. Sadly we have no idea who these people are or where they came from, but they are much more convincing than a lot of the other internet possession videos we stumbled across in this search.
3. Father Makari Yunani
Father Makari Yunani has a seemingly large following of exorcist enthusiasts. Alas we can not find any proof of his affinity for cracking the demon code on his website. However there are tons of videos of this Orthodox Priest doing exorcisms in Cairo. About 9 videos with multiple healings in each.
4. The Reading Family of Litchfield, Connecticut
In May of 2007, 20/20 did an interesting feature on possession, focusing in on the Reading family of Connecticut. Skip to 6:00 to watch this family handle mom's issues.
5. Possession in India and The Philippines
National Geographic put together an interesting package on demon possessions around the world. The two most interesting films to come out of it were the segment on India's cave of spirits and an actual Philippine exorcism performed by someone named "Kali-Mah" [not from Indiana Jones]. While we're wont to believe that the story from the Philippines is merely a boy suffering from actual trauma, we still think Kali-Mah is the most convincing exorcist we've seen yet.