This is quite possibly the most over-engineered pen I've ever come across, and it looks like it's straight out of a spycraft lab. The Hancept Zero Mk2 is a 2-mm-thick contraption that can slip into a ...

This is why they are typically used for craft projects involving rock, ceramics, metal and plastic. They tend to dry faster than water-based paint pens. Water-based pens remain incredibly ...