NirCmd - NirCmd is a small utility that allows you to do many useful tasks from command-line, without displaying any user interface: change your display settings, turn off your monitor, open the door of your CD-ROM drive, and more...

CareUEyes - CareUEyes is an eye protection software for windows that comes with blue light filter, screen dimmer, and break reminder

Yad - Yad (yet another dialog) is a fork of Zenity with many improvements, such as custom buttons...

Red Moon - Screen filter for night time phone use.

Zenity - Zenity is a tool that allows you to display GTK dialog boxes in commandline and shell scripts.

Dimmer - A very small and free utility for Windows to reduce brightness on LCD/TFT screens.