The other day I came across this:

"A study done on people treated for rattlesanke bites revealed that almost 15% of patients claimed theeir attacker was dead. One man shot a snake, cut off the body and waited five minutes after the animal had stopped moving. When he picked up the head, the head lunged and chomped down on his finger. When he grabbed his finger in pain, the head bit him again on the other hand.
The study concluded that a decapitated rattlesnake should be treated like a very short snake."

I compare this to the folk belief that a decapitated snake's head lives until sundown. Cooler temperatures after nightfall would make reptilian action sluggish at best.
I'm amazed that the head could/would still bite that long after decapitation. I know snakes have really simple brains, but wouldn't oxygen deprivation have stopped brain action at that point? How much of a bite is reflex?