I. I live in China, so pollution can be a problem at times. Usually I don't bother to check the Air Quality Index, but it's useful to know when it's really bad, so I wrote a small script to connect to aqicn API and display the index in my desktop panel (along with weather and temperature :)

II. This year my school's schedule is really hard to interpret, with 4-days rotations out of 6 every week, plus fridays also rotating themselves... I wrote a script that checked the schedule, the holidays, fetched the list of classes for each student and created a .csv file ready to be imported in their calendar. Sadly I didn't bother to build a GUI for it, so I'm the only one using it.

III. Wrote a script to automatically swith color profile in my terminal and panel. Still have to figure out how to switch gtk colors though.

IV. I wanted to use mpd to listen to music, but be able to stream some music from youtube if I wanted to. I used youtube-dl to fetch stream URLs and titles for songs, and add them to MPD playlist.