Or any skill that you deeply value for how it helps you, but maybe easily overlooked by an outsider?
I think exercising atleast 2-3 times a week was good for me. Not that I look much different, but I do feel a bit stronger and that is nice. Neck isometrics and bridges too. They really helped with balancing looking at mobile or PC screens.
Learning some keyboard shortcuts was nice. The major one would be Win key + Arrow keys to manage multiple open windows/apps.
Then, finding that I can add commonly used options to the QuickAccess bar in Excel, Word etc. Libreoffice would probably have similar options too.
Since last summer i put a series of repeating activities on my calendar, one for every day of the week. Their main effect is reminding me that my free time could be spent on personal prpjects that do not necessarily need to lead to something public.
It also encourages intentional boredom, as opposed to scrolling. I don’t know if it improved my life a lot, i end up ignoring the suggested activities most of the times, but it helps me keeping that frame of mind, and it probably allowed me to put effort in a few things i care for.