An invisible wall of super condensed jelly would make a great shield to stop bullets and sarcasm.

“An elephant walks into a bar, and the bartender asks, “What can I get for you?”…”

“I don’t just have one mustache, I have two. You can hardly notice them, though,…”

“I’m tired, and I just want to take a nap. But I want some good sleep, so does a…”

“A blanket could be used to alert your guest when he’s overstayed his welcome. B…”