No, I do not. As far as I'm concern people act like someone possessed them, are
A) have psychological/mental problems and misunderstood. Sometimes the whole "exorcism" ritual may cure their psychological needs but that's all.
B) Pretending outright to con.
And I have seen the second category a little too much. There was a Muslim majar/grave near my home. I don't know even if someone was indeed buried there or if it was a human. Just that some of the Muslim community started treating it as such and even celebrating "urs" there- which was clearly a sham. There was no way to know anything about what was in there, let alone who to celebrate anything about his/her/it.
(- My grandma said when the area was colonized there was only a dirt grave there. No one bothered to check but it was said that it was some pet, of the previous owner, buried there. But then a neighbour took upon himself to get it tiled. She even complained that that neighbor actually used the material and labour she had brought to build our family home, in her absence and got them to do so. -_-)
But whatever the back ground, I saw it's growing popularity over the years. People from other areas, used to ask me if I ever "saw" something when they got to know location of my home. Some would act impressed when they realized I regularly passed by that grave, alone, way after sun set, or sometimes at night.
I never saw anything supernatural. Not even if I went on my roof after midnight to stare down at that grave. It was only few feet away from our boundary.
But, I saw people brought there for exorcism and the whole drama a few times. Once public went away the girl who used to get "possessed" in front of the crowd and the custodian fought over money. Then she was changed. A few times I saw some poor idiot bringing there really sick child to get cured and getting the ritualistic drama taking place. I remember pitying those kids and felt like yelling at the parent to take that kid to a doc instead.
Not that I did anything. It was a Hindu majority area and the grave was being handled by Muslims. My grandma told me to shut up, keep to myself and ignore the ruckus that took place there on Thursday nights. I was told poking my head in it, or making any comments, would resolve nothing but might start riots.
That was from my childhood.
Another drama I saw a few years ago was at a temple. I had went to visit a local temple with a friend. Her brother was getting married and she wanted to consult the priest regarding it. While we were waiting for our turn, there was a family- a woman with young adults and one of them was a problem. He was making faces and acting agitated. And then suddenly started acting as what locals say possession by a spirit and started making demands.
No, I didn't buy even iota of the ruckus. His drama started right before our turn- a severe annoyance. I can bet the priest didn't buy it either, though he was mild in hinting that and mostly entertained him. He clearly didn't want to call out his bluff more openly to avoid any serious altercation, or loss of clients. The guy contitnued acting very aggressively and violently for 20 minutes or more. Priest tried to downplay the tantrum and get things back on track but it clearly affected the crowed. My friend and I watched the drama from very near but backed out ( later we left without consulting as well. She wanted to set a date for wedding but she got it later.)
I just felt that a good old spanking and locking him up in basement for a week on bread salt and water, would have exorcised the spirits away from him, just right. For life. His mother was buying his whole shit, and lamenting that her husband didn't. His brother seemed neutral. Husband clearly had opted out and hadn't accompanied them. And from what I gathered from mom's wailing and rants, husband knew his son better and mom was too gullible.
It was however a temple in outer side of the city and in an area where a lot of such women came, it seemed. The incident totally divided the crowd in two. The ones likes us were backing off and letting 'believers in that shit' take space in front. They were so attentive to whatever crap the youngster was sprouting with a mix of fear and awe. The priest talked and calmed him down and told the woman to get a ceremonial puja her son was demanding among other things, get done at her home. She went away complaining how she would have to get her husband to understand. I felt priest thought it was husband's problem anyway.
As Christians are fewer here, I never witnessed any Christian drama over it outside of videos.. closest, I can do is to quote Ruskin Bond on it- In one of his books, he mentioned tales of ghosts in Mussorrie- he said that although British were there in smaller number and mostly left India, all the local Ghosts he heard about, were Brits. He theorized ( half in jest) that either Brits living there were very restless, or the cremation ceremony held by majority is more final and complete and ghosts aren't left behind.