4. Action Comics No.1 Comics
Manufacturer: Jerry Siegel and Joe Schuster
original price: 10c*
Worth today: US$ 3.2 million*
Action Comic #1 is the first superhero comic book. It originally featured several superheroes, most notably Superman, and is credited with starting the superhero genre. It's also the most valuable comic book of all time, so it's definitely worth digging through the old box of comics gathering dust to look for one of these guys.
Published in 1938, the cover shows Superman lifting a green car as people flee the scene. 200,000 copies of the first edition were printed, which sold out at a remarkable rate. It didn't take long for them to realize that Superman was the reason for the comic's success, after selling a million copies a month.
Comic books themselves have become even more popular in recent years, thanks to the work of Disney and Sony. While an issue of this particular comic cost just 10 cents at the time, an original version can be worth as much as $ 3.2 million. This is no small thing.