If these short animations don't put you in the mood for Halloween, I don't know what will. Michel Gagné originally made these for Halloween Weekend on Nickelodeon in 2005, but some of them proved to be just a little too disturbing for kids and never aired. There's nothing explicit... they're just a little... well... you'll see. The series was recently spun into an XBox game called Insanely Twisted Shadow Planet.
Link via Laughing Squid