Nah, I want one though. Inversion has awesome benefits for the brain as well. Check this show if you ever have the time. Pretty crazy shit:
http://www.superhumanradio.com/rss/2010/SHR_Show_446.mp3
I actually invert for 10 mins before I go to sleep every night. My quality of sleep has changed dramatically.
Edit: Just noticed the link is broke. It should be updated when SHR's switch to the new server is complete.