I can crack my wrist, (probably from an old football injury) real loud. It seems the longer I wait to crack it (week or more) the louder it is. Sometimes when my wife is sleeping, I'll crack my wrist right by her ear. She'll jump up wanting to know what the loud noise was. Of course, I play like I'm asleep!
Once, at a restaurant, the waiter handed me a platter of food to pass. My wrist went into the right position and a loud pop came from it. The waiter started to panic that he might have damaged my wrist. I got a free meal out of that one!