Coins on Coins
Even though I've never pursued it, I always thought a neat collection would be "Coins With Coins". There is a surprising number of them when you start looking. If I had one, my collection would include U. S. coins, U. S. Mint Medals, Dark Side coins, and maybe even some Currency.
Here is one of my favorites because of the beautiful contrast between the field and Continental $ on the proof version.
Let's see how many different we can post.