Mike the Headless Chicken Weekend

He managed to live for 18 months after his head was totally cut off from his body. A quick check on this website and Wikipedia reveals that Mike the Headless Chicken Day/Weekend is "celebrated" every third weekend of May.

"Mike, Mike, where's your head? Even without it, you're not dead!"

"Mike's will to live remains an inspiration. It is a great comfort to know you can live a normal life, even after you have lost your mind."