What’s the most useless invention you can think of?

Obligatory:

The Useless Box

phone case for nokia 3310

The Chain-o-block-o

An immutable ledger of transactions listed in chronological order.

Wait......

Email. It was designed to make transfer of information fast and easy. So fast and easy that people will cc you on anything possibly remotely relevant. You get 100 emails in a day and you bet your ass you ignore some of the actually important ones by mistake.

Fucks sake Dan, we share an office! Just fucking talk!

Juicero was pretty bad