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Some old-school video games are worth much more than you thinkby Marc Urbino

WATCH: Here is a list of the top six most expensive video games in the world.

Birthday Mania| $15,000-$35,000

Developed by Personal Games, these could only be ordered via magazine ads. Due to low demand at the time, very few copies exist today.

WATCH | Some of the rarest Pokemon cards can fetch a very high price, as well.