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.
Well, the freezing point of water is very relevant for weather. If I see that the forecast is -1 degC when it was positive before, I know I will have to watch out for ice on roads.
And the boiling point as the other reference point makes complete sense.