They did a funny bit on that on the X-files in an episode Titled "Bad Bood". It's one of those really delightful episodes that has a lot of humor in the mix. Mulder thwarts a vampire by throwing a handfull of sunflower seeds in front of him. Ironically enough, the first hit on my google search turned up an opsessive compulsive recounting of the entire episode.

http://www.monkeyhouselounge.com/features/badblood.html