A little system to track windows open and the windows focused at the current time.
It generates a file on ~/data/desktrack.csv with columns
Date|Time|CurrentWindow|...other...windows...
Can be used for data analysis of how you spend your time.
Clone the project i.e. in ~/projects/desktrack/
and then in your .xinitrc add this lines
cd ~/projects/desktrack/
bash start.sh &
Next time you restart your X server it will start tracking data.