I chose normal laugh, but to be more precisely it has to be something between insanely loud and normal. I preffer the musical laugh, where you clearly hear the 'a' in. Just try to imagine, you'd probably know it.
A laugh which isn't controllable. If it's too loud the neighbours probably hear us, Antwerp (where I live in) is really that densely populated. I oncely had a girlfriend, who used to say thing like: "I love to be tickled, but not here" or "I love to be tickled, but I'm afraid to lose too much control" (the last one sounded like a request to tie her up).
While we never had it about our fetish, am I pretty sure she also had it. I told her I had a feet fetish, and she directly asked me if I had another fetish beside that. It was because she knew I was into tickling, it's like as if she was spying on this website (who knows).
EDIT: Oh yeah! When I told her about my feet fetish, she laughed loudly about it and considered me weird and that same day she would tease me by playing with her feet over my body and between my legs or in my face. But the slightest touch on her sole resulted in her laughing, she was really hyperticklish, uncontrollably. The first time we actually had sex, was the day she got to know about my feet fetish, though have i never told about my tickling fetish, she loved short sessions, never had the needs to tell her.