This video is indeed by me. No, I didn't use mods or hacks. Enjoy!
Please pinkie, don't care which way. Just don't skip if you watched it all!
(The tags are lying)
How to reproduce this glitch: Go up to High Hrothgar and get one of the graybeards sorta close to the cliff. Then aggravate him. He will run at you and try to punch you at first, and you should go stand right on the edge of the cliff, at that kinda slanted rim. Eventually, the graybeard will back off and use ice form on you, and you will start falling! Then, its just up to if you're lucky enough to start spinning like crazy ;D
From my experience it works about 1/3 times.