(YouTube link)
The only thing stranger than making a video trailer for a magazine article is the subject of that article... Killer Parasites. Ransom Riggs at mental_floss created this trailer completely out of public domain footage he found.
Link to Killer Parasites article (warning: not for the squeamish).
Link to video article.
I recognized the clip of the announcer from The Day The Earth Stood Still and the skeletal dog from Teenager From Outer Space.
http://www.youtube.com/watch?v=oSGrHT7cpt4
This, by the way, was pure genius.