The Ancient Greeks wish they could've used this 'digital' 3D-printed sundial

Quit glancing at your Apple Watch and go back to the original timekeeper: our faithful sun.

YouTuber and designer Mojoptix has unveiled a cleverly designed 3D-printed sundial that uses no batteries, no motors, and no electronics of any kind. With only a carefully arranged set of pinholes, the device automatically casts the correct time (in 20-minute intervals) as a shadow below.

He calls it "Cadran Solaire Numérique," and it's available to buy for $80 on his Etsy page, although all the designs are open-sourced on Thingiverse if you're handy.

In any case, it's mesmerizing in action.

Each slat in the sundial's arm corresponds to a particular angle of the sun's rays through the day. Where the light hits the slats determines which rays get cast as shadows and which appear as pixelated numbers making up the time. 

Customers can purchase either a Northern or Southern hemisphere model, and Mojoptix says the arm can even rotate to accommodate Daylight Saving Time. But the clock only works between 10 a.m. and 4 p.m., making it more of a novelty than a reliable timekeeper.

But that's OK. Novelties can be awesome, too.