Proprioception

I hate to keep linking to dinosaur comics like I'm some kind of fanboy, but this comic just keeps cracking me up.  (P.S.  Don't forget to read the mouse-overs).

I actually experienced this once, without any kind of chemical enhancement.  It occurred during a period of meditation that followed a 2-hour stretch of yoga.

(Stretch of yoga!  Hee-hee!).  It was actually very enjoyable.