Just for the challenge, just for fun, just for bragging rights, and just to do a little showing off – all perfectly valid reasons to take on a project. It seems like one or more of those are behind this tiny ESP32 board that’s barely larger than the coin cell that powers it. From the video below, [Mike Rankin] has been working down the scale in terms of powering and sizing his ESP32 builds. He rec
![A Coin Cell Powers This Tiny ESP32 Dev Board](https://cdn-ak-scissors.b.st-hatena.com/image/square/a72cf3f8afe42c86ff391e83605511ef1dfdc028/height=288;version=1;width=512/https%3A%2F%2Fhackaday.com%2Fwp-content%2Fuploads%2F2019%2F02%2Fesp32-pico-d4-coincell-board-2-7-screenshot-e1550019481367.png)