There's not a single college in the country that will let you use this wooden calculator during an exam. And it's not because it can be used for cheating. It has more to do with the fact that instead of pressing number buttons, you have to tap out your amounts on its wooden surface, and it will in turn tap out an audible response.

Not to mention, since Khalil Klouche actually designed the Knock Knock calculator for kids, it's lacking any operations more complicated than basic arithmetic. So while it won't improve a child's grasp of exponents or algebra, it will certainly do wonders for their counting skills. [Khalil Klouche via CreativeApplications]