The In-house Mad Hatter

Jan: *chuckles*

X: What's so funny?

Jan:
Twinkle, twinkle, little bat!
How I wonder what you're at!
Up above the world you fly,
Like a teatray in the sky.
Twinkle, twinkle little bat!
How I wonder what you're at!

X: Where on earth is that from?

Jan: The Mad Hatter in Alice in Wonderland.

X: Did you know where that came about from?

Jan: What?

X: The chemicals used to hold the shape of felt hats. That contained something that made the hatters mad.

Jan: Didn't you used to be a hatter?

X: ...