IntelliJ shows me a notification on MS Windows when the tests are done. (At least if it is not in focus). This helps me bring back my focus if I switched it away.

I would like to have a similar for my command line on Linux. Either running the commands with some prefix or automatically on every command on the terminal. Maybe on every long running command. 

notify-send Done "$command"

I even created a file called not with the following content: 

#!/bin/bash
command=$*
#echo $*
$*
notify-send Done "$command"

I put it somewhere in my PATH and made it executable chmod +x not.

Now I can run 

not command

and I'll get a notification when the job is done.