Last year, I made a simple timezone bot for Discord.
My school friends and I had been living increasingly remotely since we all graduated, and it was getting harder and harder to track who would be awake when, and when you could expect a response from someone. So, I got to work making a simple tool that would allow users to set their timezone, and then passively and unobtrusively notify users of their partner's local time when they were talking to someone in another timezone.
After a year of running a single-server version and getting dozens of emails from interested server owners looking to use the bot on their own server, I finally made a live version that anyone can add!
If you're interested, add it to your server!
Also, let me know if you have any questions about Discord bot development.
You can read more about this project here, and have a great day! :)