Is that a gun in your pocket, or are you just glad to see me?

Here's a variant, Cap..
A renowned wag at work (call him Bill), on seeing another colleague (Ben) walking back from the canteen with a banana in his pocket, piped up:
"Is that a banana in your pocket, Ben, or are you pleased to see me?"
to which came the reply:
"It's a banana, Bill - I'm never pleased to see you."

Blinding.