JAM-
I've seen
Harold & Maude! The 1st time I saw it was near the end of my sophmore year of college. I was hanging out with some friends & one of my Phi Beta sisters insisted we watch it- it was her favorite movie & none of the rest of us had seen it. We were mostly like this:

the whole time!
But I don't wanna give anything away. Definately a good recommendation, though!
As for my fave cult movies:
Probably
The Breakfast Club & most of the Monty Python films
My fave B movie:
The Lost Boys