Cracking your Knuckles

[EpicGamer12]

Wrists, fingers, knuckles, neck, toes, and ankles.
My sister hates me doing it, but I can't resist.

 

[muffun]

I don't mind other limbs and joints, but for some reason cracking knuckles makes me want to cower in a corner. It's not a phobia, but it freaks me out incredibly.