Our friend Yehuda Kleinman writing over at the Star Wars Collectors Archive takes a look at pressed pennies and elongated coins, of which there are a surprising amount.
Pressed pennies, squished cents or elongated coins are the names given to kitschy souvenirs that can be self-manufactured by a tourist or visitor at a locale with nothing more than pocket change and occasionally some elbow grease on a classic hand-cranked machine.
The different machines that create these collectibles can be manual or automatic but all follow the same basic principle: transforming standard round pocket currency into oval flattened souvenirs with embossed images of interest, often commemorating the activity or place where the machine is located, or at times depicting an individual or character.
It’s a great article, so head on over there and read the article in full.