Since their introduction in 1964, Sharpie’s have been a useful marking tool. They come in several varieties and are used to permanently mark many types of surfaces. Sanford, the makers of Shapies, recently introduced an innovative “liquid pencil“. It is like using an ink pen, except with all the benefits of writing with a pencil. It uses a new liquid graphite technology that is very durable and equivalent to a #2 lead. Forget broken leads and no more sharpening. It is also refillable. A valuable tool for those unending math tests.