To damn right mate, mine was sent to me by Eamonn, I made it up when doing trial testing when I worked in the postroom.
A little experiment to find a pen that would write on anything and be fool proof as there were lots of fools using them.
Never did beat the cheap plastic biro that come in packs of 100 for a knicker but never finished the experiment either.
Dunno what they use these days whether it's my pens or the plastic ones init?