Unveiling the World's Most Valuable Collectors' Items

3. Rubik’s Siamese Mate Cube (Original Price: $4* Worth Today: $100-$125*)

If you thought solving a regular Rubik's cube was challenging, wait till you meet the Siamese Mate Cube. It's a true head-scratcher! Created by Tony Fischer back in 1982, this peculiar puzzle consists of two Rubik's cubes joined together at an angle. The cubes overlap each other, making it impossible to solve the side where they are connected. However, the other sides still need to be cracked to conquer this mind-boggling puzzle.

During the Rubik's cube craze of the time, these Siamese Mate Cubes were available for purchase. However, they weren't produced in massive quantities like the standard Rubik's cubes. Nowadays, if you browse eBay, you'll find original Mate Cubes from the 1980s being sold for around $100 to $125.