There is a scene in Peep Show where Mark's favourite mug is smashed. His boss comes in and says:

"I'm sorry about your mug, Mark".

However the first time I saw it I was 100% sure he said:

"I'm sorry about your Mark, mug".

I thought it was a subtle joke and that the boss had accidentally swapped the two words without realising it. I thought I was clever for hearing the joke and I laughed and laughed because, well, Mark is a big of a mug.

Anyway I found out later that I was totally incorrect and now I laugh at a non-funny line that was just part of a conversation.