It's good for the back
I first used one of these while getting a haircut at Sport Clips.  This thing is amazing and so I decided to get it for personal use (on my back).  Get your mind out of the gutter folks.  It comes with three attachments for the back, scalp and for a finger massage if you need one.  It doesn't overheat and helps reinvigorate me after long hours on the computer when my back hurts.
Rating: 5 stars