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.
I remember using Xiph’s integer implementation of Ogg Vorbis on my Nokia N-Gage (Symbian S60). I wonder if it’s not a priority for Opus. IIRC, Opus is floats all the way down.
update: it exists.
https://wiki.xiph.org/OpusFAQ#Is_there_a_fixed-point_implementation?
I remember trying to understand Vorbis fixed point codebase, it was completely bonkers, the three of us on this task couldn’t even draw a rough control flow diagram.