Switch display resolutions or adjust your screen brightness and colors (time-based) from the menu bar.
Check out these Mac Menu Bar Display Apps:
LightsOut
This menu bar app allows for disabling monitors with a simple button click – no more cable fidgeting.
Gamma Dimmer
This menu bar app lets you dim the brightness of all your screens without compromising color accuracy.
Display Arranger
Tired of having to adjust your settings whenever you move your displays? This menu bar app allows you to quickly configure where your monitors are in only two clicks. Plus, you can save particular arrangements.