Wow, I've found out that there are a number of float spas quite close to where I live. I won't be surprised if the concept catches on and becomes more popular. Actually, the only aspect of the float tank I'm not very fond of is that once the lid is closed it's completely dark. I'd prefer a light...maybe the way it feels to lie in a tanning bed. But, I understand too that the darkness is a part of complete sensory deprivation. Anyway, here's a good link:

FAQ | Om Float Spa

Oh - wait - there are some tanks that use infrared light while you're floating. I would like to try this place this summer (about 85 miles from where I live): http://www.floatmatrix.com/index.php/ir-sauna