The world's largest note (file photo)

Top 6: The world's largest note

In 1946, Hungary fell into the most serious inflation in history. The then government issued the 100 Million Billion Pengo -- a world-record denomination. In fact, it was only worth about 20 US cents.

The unlikeliest Kennedy coin (file photo)

Top 5: The unlikeliest Kennedy coin

Mongolia issued the 500 Tugrik coin in 2007, with the image of former US President John F. Kennedy displayed on the back. What is even more impressive, is that when pressing a tiny button on his chest, you could hear Kennedy himself recite his famous "Ich bin ein Berliner" Speech. Once the coin was issued, collectors snatched up the largest batch of its edition almost immediately.