Fourier
Permanent link to this comic: http://xkcd.com/26/
Image URL (for hotlinking/embedding): http://imgs.xkcd.com/comics/fourier.jpg
[[ Person talks on phone. Cat with many sharp points looks on. ]]
Person on phone: Hi, Dr. Elizabeth? Yeah, uh ... I accidentally took the Fourier transform of my cat ...
Cat: Meow!
{{alt-text: That cat has some serious periodic components}}