Screensavers are one of the often overlooked, and useful pieces of software your computer can run. As well as potentially preventing screen burn to your display, they can also relax, entertain, and inspire you.

I've done some research into the screensavers that will 10x your computer's aesthetics when not in use - and also provide, in certain cases, some useful functionality.

My top 3 recommended macOS and Mac OS X screensavers has to be:

Fliqlo is a clock screensaver from Yuji Adachi, a Japanese developer. It utilized a simple concept, replicating an old-fashioned, electromechanical flip-clock similar to those that were popular back in the day. The clock displaying the time in bold, white numbers against a solid black background. Options include scaling of the clock to suit your display size, and switching 12/24-hour time formatting.

Padbury is the cleanest design you're likely to find. It's a minimalist digital clock screensaver from Australian-American designer Robert Padbury that displays the current time in an elegant, thin font. It has the option to toggle between 12- and 24-hour formats, and has a night time mode that sets the font color to red betwen 10 pm-6 am. There are dark, light, and alternate themes.

Aerial is a Mac screensaver based on the Apple TV screensaver that displays the slow-moving aerial day and night movies that Apple filmed over New York, San Francisco, Greenland, Hawaii, Hong Kong, China, and London amongst several other locations. The scenes also seem to update over time, adding that unpredictable feel.

Customization of your screen saver can be found from the Apple menu > System Preferences > Desktop & Screen Saver > Screen Saver tab. This applies to macOS High Sierra, but should be the same across the majority of OS versions.

GitHub user agarrharr has compiled this useful list of a number of popular screensavers for Mac OSX below. Check 'em out.
A curated list of screensavers for Mac OS X

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