[Giganticface]

I'll hopefully help seal the deal on two great films that others have made compelling pleas for:

Return of the Living Dead
Near Dark

[Edit]
I'll also back Demons because those demons are straight up rabid.

I'll also back Sleepaway Camp for being so unique in so many ways -- the real child actors, the screwed up exploitative themes, the terrible, Basket Case level, acting, and of course the WTF ending that you couldn't forget, even if you wanted to.