This little device could well change the course of history.

[Yelta]

Perhaps it could be adapted to some useful application in the coffee industry.

The Most Useful Machine EVER! - YouTube

[MrJack]

A) Where do I get one
B) How much are they
C) Will it improve the extraction efficiency from my TSV nanopore naked portafilter, if paired with an ultra smooth TiN coated Zerogap tamper?
D) Is it more useless or less useless when the batteries run out?

[kwantfm]

Mesmerising...

[flynnaus]

Perhaps it could be adapted to some useful application in the coffee industry.

You will never turn your coffee machine off accidentally.

[saroadie]

Perhaps it could be adapted to some useful application in the coffee industry.

The Most Useful Machine EVER! - YouTube

What were you looking for when you happened upon this I wonder?

[noidle22]

A) Where do I get one
B) How much are they
C) Will it improve the extraction efficiency from my TSV nanopore naked portafilter, if paired with an ultra smooth TiN coated Zerogap tamper?
D) Is it more useless or less useless when the batteries run out?

You can get them as kits online for about $40 or a prebuilt one from China for a bit less. I think the fun is in building it as well as watching it work.
To your other questions, the answer is yes.