My favourite is using emojis for classes. It's pointless but I think it's funny and that's gotta count for something right?
Someone in my team once used an emoji in a commit message and took down our CI.
The next week I see a string of poop emojis in some pull request commit messages. I talk to the dev who wrote them and he was testing a CI fix so it doesn’t go down if someone commits emoji again later.
A true highlight of my career.