4K Fun Pun Race for the Punchline

So I'm approaching my 4,000th tweet, and it's going to be a joke. I've held a long and proud tradition of Twitter puns, and the 4,000th entry will be no exception.

Here's the deal: I need you to come up with the subject matter and/or punchline, and I'll have to set it up in 138 characters (to fit in "#rimshot" & provided I choose your idea). The winner receives internet immortality and the satisfaction of a joke well crafted!

Some examples of my past work:

The script called for molten metal to be poured into a mold of a capital G, but the iron was just tired of being type cast.

The Greek deli asked Peter Parker to dress as a giant sandwich for a promotion, but he didn't want to come across as a supergyro.

The carny thought he should replace his old hubcaps with new iron ones, but he'd had his fill of ferrous wheels.

Say what you like about Congressman Raisin's policies, you have to admit he's up on currant events.

Before the full list of paternity suits was compiled, the king had not known such a breadth of fresh heir.

The warehouse was full of tacky plumbing fixtures; it had everything but the kitschy sink.