OK, this is fucking awsome. And that's just while straight. Wait till you do it with some X in ya!
OK, you need two people for this.
Have the person who is rolling (assuming at least ONE of you is on E

) lie face down on the ground (ie. on their stomach) with their arms outstretched in front of them (as if someone had just yelled "Stickem up!") and make sure their eyes are closed, and that they are limp and relaxed. This can be called person A.
Have the other person (Person B) stand at the hands of the person lieing down. Have Person B take the hands of Person A, and pull them up so they are supporting their weight and Person A's body is on a sort of bent incline. Their hips should just be off the ground but their legs should still be semi-flat on the ground. Their arms should be paralell and have person A look down towards the ground, their eyes still closed.
Now, once Person A's head is lifted about a foot off the ground (doesnt have to be exact), have person B VERY slowly lower them towards the ground, meanwhile repeatedly telling them where abouts they are in relation to the ground in a soothing voice.
"You're floating down very softly towards the ground....it's coming up...you're almost at the ground..."
But soon begin to tell them they are about to go through the ground (Do this about half way towards the actual ground). Act all excited.
"Oy dude, you're going through the ground! When are you going to stop?! OMG! the ground is above your head! I'm up here man!"
It's an awsome sensation, and it can be felt without being on X. I first felt it when I was straight, it blew my mind. It's a real spinout, it actually feels like you've gone through the ground!