Every so often here at HuffPost Culture we come across some piece of art or design that's kind of cool, fun to look at, but doesn't really serve any kind of purpose as an object of discussion.

There are quite a few of these pieces floating around-- so many that we decided to dedicate a new weekly feature in their honor, one we're calling "Useless/Cool."

This week's Useless/Cool thing comes to us courtesy of DesignTaxi and Pittsburgh-based designer Karl D.D. Willis (that extra D is not a typo, promise.)

It's called a "Moire Card" and it's essentially a masking device that slides over your business card, "decoding" gibberish symbols and making them readable. It's also basically unnecessary unless you're some sort of international spy, which if you are: you really ought to buy a Moire Card, because you're going to love it.

Check out the demonstration:

Willis -- currently a Ph.D. candidate at Carnegie Mellon who also works for Disney Research Labs -- likes to explore the playful qualities of technology in his projects. You can check out the rest of his work, like his equally cool Motion beam, by clicking here.