I once went a couple days without cracking my neck, and it was getting really achy and stiff ... I was stood in the line at a bank, and I just had to crack it ...
So, I whipped my head around, in the motion I use to crack it, and it was a long, bone-snapping kinda sound ... really loud ... serious horror movie sound effect quality ... and the girl behind me fainted lol
Insta-win!
Here's some info on the subject:
http://en.wikipedia.org/wiki/Cracking_joints
QUOTE(wiki @ Apr 24 2008, 02:13 AM) Dr. Donald L. Unger spent fifty years cracking the knuckles of only his left hand twice daily. After this time his hands were found to have no noticeable differences and no arthritis had developed. The common parental advice "cracking your knuckles gives you arthritis" is not supported by any evidence, but habitual knuckle crackers are more likely to have hand swelling and lower grip strength attributed to stretched tendons.