Egg -- Somehow I doubt the Penny Note will gain traction. If however you wish to be an early adopter I'll record you in the blockchain as the owner of 600,000,000 of the Pennies. My gift to you.

Keith -- The guilloche approach I used was to simply superimpose two different blends of lines. I started with a wavy line (created as a sine curve), duplicated it and made a blend. I then cloned that blend but stretched and squished it so it was different than the original blend. So the guilloche effect is simply created by seeing the two sets of blend lines and their visual interaction.