I've been taking note of the different ways laughter is spelled by my online Portuguese-speaking friends. One spelling is "rsrsrsrsrsrsrsrsrsrsrs," which to my ear is more of a snicker than a chuckle. Incidentally, another popular spelling is "kkkkkkkkkkkkkkkkk." Em fim, finally, there's "asuhasuhasuhasu!" I have no idea how that's supposed to sound, but it features a few vowels which leads me to think it's a bit more booming than the other two.
A scene from The Simpsons comes to mind. I can't remember the exact episode (sorry, comic book guy), but it involves either Lisa or Bart interrupting a French class in Shelbyville. The teacher, of course, is a beret-wearing, prison-stripes Frenchman cliche. The children laugh in the usual adolescent American idiom: "heeheeheehee," but are stopped by the gruff teacher, "Non on on, en français!" And so the children recommence: "ron ron RON!"
In one of my first French classes, before the professor entered, I asked my fellow students if they had been practicing their French laughs. They looked puzzled. Then I broke into a loud "ron ron RON!" They laughed in English.