This is a puzzle box I built to infuriate my friends. There is a secret to opening the box that is very, very hard to guess. People will spend hours trying to open it. It is a perfect 1.25 inch cube with only a single seam around the middle.There are two elements. The first is the actual locking mechanism. The second is a pure distraction to keep them from finding the first mechanism.The box is locked by a ball bearing being held in place by a magnet preventing the box's lid from rotating. You can't discover or manipulate this magnet unless you apply a very large acceleration to the correct face. If you hit it on the table you break the magnet's hold on the bearing and the bearing moves to an empty space allowing the box to rotate open.There is also a set of three smaller bearings that roll around in a set of three tracks. They do nothing but you can hear them and you can move them. This is a red hearing. People will fixate on manipulating the bearings inside the cavities that they will never try smacking the box. Hilarity ensues as they get more and more frustrated that nothing works and they hypothesize more and more complicated internals as reasons for their failure.WARNING MAY RUIN FRIENDSHIPSHow to open boxI bought my magnets from amazonhttp://www.amazon.com/Magcraft-NSN0732-16-Inch-Magnets-40-Count/sim/B000E683XQ/2 But they don't seem to be available anymore. Here is a replacement but feel free to use a different magnet. Edit the parts files as needed.http://www.amazon.com/Applied-Magnets-100-Neodymium-Discs/dp/B001LQQP9W