A Chinese plumber, dubbed China's "Useless Edison," has become an internet sensation with videos of his wacky inventions, like a meat cleaver that doubles as a cellphone case, or a scooter with a built-in toilet, which flushes when you pull the lever on the handlebar.
(No word on where it flushes to. A word to wise: Don't ride behind him.)
He makes his money from ads on his website and not on sales of the products, which is lucky because he couldn't get a patent on them.
To get a patent, you have to prove that your invention is novel, non-obvious and useful. If the invention isn't the first of its kind, it's not novel.
And just because no one has thought to, for example, patent a hammer, doesn't mean that you could get one — it has to be non-obvious, unique.
Finally, the invention must be functionally used and have a purpose — so much for Useless Edison's slippers made from metal nuts.
But he's undeterred. "People say my inventions are useless. I like doing this. So, it's useful."
Even if the U.S. Patent and Trademark Office wouldn't think so.