How do you tell when youโre out of invisible ink?
The other day I ... no wait, that wasn't me.
I am writing a book. So far I have the pages numbered.
For my sister's 50th birthday, I sent her a singing mammogram.
I have not lost my mind - it's backed up on disk somewhere.
If a tree falls in the forest and no one is around to see it, do the other trees make fun of it?