You know what? This movie is pretty different. I'm well acquainted with both cult movies and the b-movies made out of love for them, but this one truly gets into the spirit of the movies it's homaging while maintaining its own unique approach to the form. I'm not ashamed to say I like this movie very much, no matter its faults.
Two parts "Invasion of the Body Snatchers" and one part Anthony Mann, "I was a Zombie for the FBI" plays basically as you would expect: with its tongue firmly in cheek and with every frame a love poem to a filmic conceit. Two brothers play cat and mouse with FBI agents as they try to steal the formula to a popular Cola that has industry spreading across the country. An alien (or more?) appears and starts taking over people in the Cola factory, further complicating things with their classic, pre-Romero zombie-like dazes. The main FBI agent has a reporter girlfriend thrown into the melieu... zaniness and awesomeness ensue.
The DVD edition of this movie is a weird mix of original footage and additional special effects. Because of the sped-up nature of the editing for the DVD release, the movie is given slightly less room to really breathe, making a lot of its beats fall flat. Nonetheless, I actually disagree with a lot of the other reviewers and say that I rather like the added visual effects. It adds a level of Boris Karloff into the already delicious mix, and I don't think it's overdone at all.
Anyway, as cult-homage films go, it could be worse. It's best quality is the closeness of sensibilities to its original source.
--PolarisDiB