Ninja.
I had a semi-dream recently, right before waking when I knew I was sleeping and dreaming, in which I made up a joke. The punchline was "This is where the nincompoop." I don't remember it exactly, but it had something to do with ninjas pooping.
Doesn't quite rank with other jokeless punchlines, such as "Gladiator," and "Rectum? Nearly killed 'em!" But it makes me laugh.
"Gladiator? He hardly knows 'er!" and "Rectum? Nearly killed 'em!" aren't jokeless punchlines, they're just punchlines that have been disconnected from their setups.
I once tried to make up a joke involving ultramontanism, "54' 40" or fight", and protestantism, but it didn't work out.
For jokeless punchlines, I always liked "Thank God I'm an atheist". ;o)
- OLS
Those are punchlines-as-jokes. Here's a real jokeless punchline: "Hey, look. A talking dog!"
Actually, I guess that one has a joke. Here's a real jokeless punchline: "Someone ate my sandwich!"
Is there a difference between a "jokeless punchline" and a "sentence"?
(I started to write a comment yesterday about the short distance between whimsy and madness, and now you've sucked me in. Damn, you, ogged.)