Turning on lights is boring, the "Calculating Chalkboard" is not. Though not very practical, it will keep guests entertained. Continue reading to see more. Click here for first picture in gallery.
Overview
Called the "Calculating Chalkboard", this gadget can be mounted on any wall and doubles as a light. The concept is simple: its built-in LED display shows a basic math problem and users solve it to turn the light on.
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