Is this going to be a Weed Cops appreciation thread?
It's kind of hard to classify a brickfilm as being "cult," since brickfilming itself is, as Nathan Wells has said before, like a niche within a niche. I could easily name some of my favorite lesser-known/not-often-talked-about brickfilms, but I doubt many would really consider them "cult..."
Especially since a fair few of them where contest entries that, while not placing highly, would likely be recognized immediately. (Especially to those of us who may have competed in said contests)
I think more specific guidelines are necessary for such a thread - since it is such of a subjective thing.
For example, would Le Special count? How about Loyalty? And Men Loved Darkness? or Caleb Christofer's great Batman brickfilms?