One leading manufacturer of pens offers a liquid lead mechanical pencil. The graphite in this case, is in solution, behaving much like ink as it rolls from the ballpoint-like tip. However, once the fluid is absorbed into the paper and dries, only erasable graphite is left. This mechanical pencil purportedly writes with the fluid motion of a pen, while offering all the advantages of a pencil. It retails for less than $3 (US dollars), and is refillable.