macOS Screensaver, v10.8+
$25 /  Buy now . . . 

Given the most commonly used criteria of *utility* for software, it’s not surprising that the screensaver is a debased form. It does nothing, it says nothing and it takes you nowhere. Instead it offers a quiet, even ambient portrait of a system — a simple image, a complex algorithm, and an ever-changing picture of their interaction.

Still there may be something to doing nothing. The computer, Alan Turing’s universal machine tirelessly capable of emulating the behavior of any other tool, is finally given a rest. After three minutes or so of nothing, the screensaver kicks in and the software produces a silently reconfiguring image of a system falling into and out of phase, automatically generating a fleeting picture of interference and coordination on your computer screen. Perhaps there is something left to save.

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