I grind my teeth but my dentist said all migrainuers do, so I don't know if this is a symptom of Aspergers or migraine, predominantly.
I also crack nearly all my joints (neck, shoulders, spine (lower back) knee caps, ankles, wrists, fingers, left big toe and foot (not right)).
I also have sort of cramps in my calves at night, relieved by pointing my toes downwards as far as possible, which causes a kind of discharge of energy at which the toes curl back up! (Don Juan in Carlos Castenadas books says this is where we store the energy of travel).