Who uses it: Monetary economists
What it means: The creation of value by printing money (or stamps, or other articles that store value). One definition is the difference between the cost of the raw materials of the coin and its face value, but seignorage is also the unspent value of currency, stamps, or things like Metro farecards.
How you can use it: To describe invisible value added.
Without going into details about this week's project, I've spent a lot of time handling old coins. I'm stupid about money, in any real sense, but I'm fascinated by the processes of it, and how necessary it is to governments.
A 1939 Reichspfennig is gold-colored, made of shiny brass; by 1941, they'd started making them out of zinc, because heavier metals were all going to war production. Many European coins in the years right after the First World War were made of aluminum, and they feel (and look) like play money. Modern Chinese coins might be aluminum, or they might even be some kind of plastic -- I can't tell just by touch.
I'm headed down to New York this afternoon, for a small dinner (a very small dinner, as it turns out, but quality trumps quantity) with friends. Back to Connecticut tonight, and on the road again tomorrow morning.