Comment from Understand the Times:
UTT recommends that your read this article published by Charisma Magazine... 
I've been writing a series on some of the controversial subjects that come up over and over with people who are opposed to Bethel or that misunderstand our position on certain issues. Check out a previous article here. Today we will talk about falling down and holy laughter.
Another manifestation that is more prominent, but equally hard to explain, is people falling down or laughing hysterically for no obvious reason. We call the "falling down" experience being "slain in the Spirit." This happens often when we lay our hands on people to pray for them (although it happens in other situations also).
Sometimes people just seem to fall over backwards as if they just passed out. Some are conscious, while others act as if they are asleep or in some sort of trance. They most often fall backwards (I have no idea why). It has been happening for so long that we now station "catchers" behind people when we pray for them so they don't get hurt when they hit the floor.
When the people who have been "slain in the Spirit" get up off the floor, they frequently share testimonies of experiencing God in some incredible way. I personally have never had this experience myself, but I have watched thousands of people fall down when I am praying for them. Could they be faking? No question, some are. But if you have ever witnessed this phenomenon personally, you would see for yourself that many of these people fall in such a way that if someone didn't catch them, they would bounce off the floor. In many cases it would be impossible to fake this kind of fall.
Could it be the devil? If it is the devil, he is doing a wonderful job of helping people get closer to God. In almost every case where people have been "slain in the Spirit," they report being more convinced than ever of God's love for them. This may all sound strange, but it's no stranger than many things that people experienced in the Bible.
One of the manifestations that has been most offensive to people is something we call "holy laughter." This condition occurs when, for no obvious reason, people just begin to laugh hysterically as if they are drunk. Some laugh so hard that they literally fall on the ground.
Weird you say? Yeah, I agree, it looks that way to me too. I love what Angela Monet said: "Those who danced look quite insane to those who didn't hear the music." I think this quote applies here. Again, it's very hard to attribute this to Satan when the fruit of this manifestation is always positive in the people having the experience.