L.l.a.f.
L. l. a. f. is when you’re so tickled you look like you just saw your pet chicken get hit by a truck. Usually happens when you're wasted, high, or just plain idiotic.
I laughed like a fuck when my brother told the joke about the toilet and the chicken.
At the concert, I laughed so hard I fell off my chair.
My friend laughed like a fuck when I told her my dog tried to wear my pants.