one of my ex girlfriends had this laugh that was to die for, if it was a good one it usually started off with her being silent because her sides were about to be in massive hurt from sucking in so much air, then she'd unleash a ridiculous "sand people" war cry.
not kidding, in the slightest...it was the weirdest thing ever, but holy hell was it so fucking funny when she was crying from laughing, you would swear sand people were raiding the next door house XD
we finally recorded it one time and showed it to her, and she had NO IDEA she laughed like that, after that she got super self conscious about the laugh lol, but she's gotten over it since then.
also, any laugh that has some kind of high pitch squeak in there, usually involuntary but always ends up being funny