Shell script to control brightness of all monitors on Ubuntu
Add to your home's bin dir and chmod +x, then:
brite up|down
increases|lowers the brightness by 10%brite nite
switches on a night mode (30% brightness)brite day
returns all screens to 100%brite opt 1|2|3|4|5|6|7|8|9|10
sets brightness to the given number x10
Original Author: Jacob Vlijm
Source: https://askubuntu.com/a/672670
Modified by: Michal Zdrojewski (added nite|day|opt
)