There are a couple I have in mind. Like many techies, I am a huge fan of RSS for content distribution and XMPP for federated communication.
The really niche one I like is S-expressions as a data format and configuration in place of json, yaml, toml, etc.
I am a big fan of Plaintext formats, although I wish markdown had a few more features like tables.
Also whole degrees.edit: no, that’s wrong, there are thermostats that allow 1/10th of degrees (I only have old manual ones). Still, you probably are not able to tell the difference between 20 and 20.1 °C. Humidity is far more relevant.A difference of 2 °F is 1.1 °C…