Don't Ask Don't Tell (2002)
Don't Ask Don't Tell is a 2002 parody film directed by Doug Miles and written by famed gay screen writer Tex Hauser. The 2002 winner of the Boston Underground Film Festival (BUFF) Bachus Award, The Neuchatel Sci-Fi Fest Audience Choice Award, and much critical acclaim for its razor sharp, if quite demented social satire, it was created by taking an old sci-fi movie — Killers from Space — overdubbing the soundtrack with humorous dialogue, and adding some new scenes, essentially turning it into an entirely different movie. The plot involves alien invaders with a machine that turns straight people gay.
More at Wikipedia.