Tempest!

Tempest! Art of Nature brings you shockingly beautiful lightning video from around the world.

Tempest! is great for those who don’t want a CPU hungry screensaver running all the time but instead appreciate a gentle artistic reminder from time to time that the machine is still awake. Tempest! runs cool because your CPU rests between lightning strikes.

For best results use a large screen in a dark room. Thunder and rain have been added by popular request. Some people find Tempest! an aid to a meditative state of mind.

"A gem of the Mac App Store" ~ applesfera.com

A separate screensaver launcher can be downloaded from the "View" menu in the app.

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If you have old Quicktime components on your computer, they can interfere with video playback of this and all other video apps on the Mac App Store, there is a free app on the store called SandboxCleaner that can check your system for this.