Silkworm son: "What's for breakfast?"
Silkworm dad: "NANOTUBES."
Silkworm dad: "NANOTUBES."
I feel bad about the downvotes in individual cases, but the culture of easy, repetitive, or just plain bad jokes is a big part of what turned Slashdot from my favorite site into a cesspit that wasn't worth visiting, so I think they're a necessary mechanism.
The trick for this site is to make a good joke. If the topic is well-worn, it has to be a great joke. If you're not sure if it's a good joke, it probably isn't. I base this on the fact that most people simply aren't funny. There's no shame in that, it's just true.
I'm assuming the OP joke is a reference of some sort since I don't get it. A good rule of thumb is that references aren't jokes at all, they're references, so posting them here will probably get you a downvote. This is also true of puns and memes, both from broader culture and more traditional nerd quarters.
And just to be clear, I didn't downvote the OP, but I would have if it weren't already grey by the time I saw it.
People sometimes post bad jokes on HN for the same reason they tell them in face -- feeling lonely, sometimes desperately lonely, maybe even feeling rejected, trying to be part of it, knowing the joke is not so great but trying anyway.
And you know, if I can somehow help those people, even at risk of being biased in the wrong direction, I couldn't care less if HN becomes Shashdot. Every forum lives its life and then dies, and we all move on.
But that's me, others are entitled to other opinions.
I think it was around 2000 or so that I set my Slashdot reading preferences to automod Funny posts -1. That turns +5, Funny "insensitive clod" jokes into +4s, allowing the +5 Everything-besides-Funny posts to bubble up to the top. It's features like that that make the original Slashdot discussion system still the best ever invented (well, back when the meta-moderation worked like it originally did, where you randomly approve or reject moderations, rather than re-moderating comments out-of-context, which isn't meta-moderation at all).