The Amazing Thing That Happens When You Disconnect | Dr. Justin Feinstein | TEDxSalem
This is one of the most famous, most popular videos out there from Joe Rogan.
Here is a great documentary on floating. Took a few years to make and is very very good.
Sensory Deprivation Tank Improves Sports Performance & Learning
Former UFC Champion Jens Pulver's First Float Tank Experience at Sydney Float Centre
The 'Basics of Floating' by Theta State Float Center (Original)