what's your favorite gadget you own that many people probably don't?

https://www.saleae.com

It’s such a simple and well built device

I dig old computers and used bookstores. 

creating and destroying; built flying cars & autonomous vehicles, now building /faust, more here: /july, web: july.rocks

Building https://srcbook.com // creator of the https://blockchainsmokers.xyz

Debugging UART / I2C lines, checking to see is my software sending the actual bytes or did the data sheet lie to me (it’s actually me who misreads it usually)

Do you use it? Do you have an example use case? Cc @whatrocks