We all have seen movies that are so bad they are actually good. For me, there are these two: MetalStorm and, since I'm from Mexico, Santo vs. Las Mujeres Vampiro (Santo vs. The Vampire Women). The first one a sci-fi/western hybrid that takes itself so seriously it was kind of funny, the second one an attempt at "horror" mixed with cine de luchadores (luchadores films) that results in such a badness that is actually pretty enjoyable.
These are mine, which are yours?