Nintendo Campus Challenge 91 [Nintendo NES] – Price: $23,100
Nintendo held a video game competition in 1991 that traveled to college campuses through-out the USA. Players competed on a special game cartridge that allowed 6 minutes to play Super Mario 3, Pin-Bot, and Dr. Mario. After 6 minutes you received a high score and winners in each location were invited to a final event to crown the champion.
After this competition was done Nintendo destroyed all the cartridges, but one was found at a garage sale in New York. It has been sold to several different collector’s and the highest recorded price was $20,100. If all of these were supposed to be destroyed but one survived, maybe more of the original 30+ cartridges are out there too.