Sometimes when I feel like killing someone, I do a little trick to 
calm myself down. I'll go over to the person's house and ring the 
doorbell. When the person comes to the door, I'm gone, but you know what 
I've left on the porch? A jack-o-lantern with a knife stuck in the side 
of its head with a note that says "You." After that, I usually 
feel a lot better, and no harm done 


-- Douglas Adams, The Restaurant at the End of the Universe