Xanadu: Wow, it's hard to find the words for this movie. 80s, neon, go-go boot rollerskates, Gene Kelly, Olivia Newton-John, dancing, bad special effects, animation....it's a wonderful if sort of awful combination. Something about the 80s made bizzare things like this work.

Stalag 17: Billy Wilder's movies are well known for being darkly comedic, I've heard it had to do with what happened to his family in WWII, anyway this movie is very darkly comedic. Hogan's Heros is loosely based off of this movie and leaves out a lot of the blackness. William Holden plays a cynic p.o.w in the German Stalag (Prison) and when it's discovered that someone is leaking information to the Germans, Holden's character gets the blame. This movie is very dark and serves as a good warning against jumping to conclusion in judging people and jumping on a mob mentality.