For more fun (and my current example), here's my script:

echo "" ; while [ true ] ; do ls -l backup.tar.gz ; ls -lh transfer.tar.gz ; df /var/backup ; df -h /var/backup | tail -n 1 ; print "\x1B[6A" ; sleep 0.5; done

That's my "comfort monitoring tool": seeing bytes values rise to have an idea of the current bandwidth, but also the "human-readable size" of these backups, and the space it occupies.

Using "sleep" after it helps in making the process less greedy on cpu+disk resources.