10. McGwire's 70th Baseball Home Run
Manufacturer: Unknown original price: US$ 6* Worth today: US$ 3 million
Mark McGwire is known as "one of the most powerful hitters in baseball in the 1990s" and set a record with 70 home runs in a season in 1998. This baseball was the one he used when he hit his 70th home run of the year, consolidating him the baseball hall of fame.
In January 1999, the ball went on sale. It was bought by a then-anonymous buyer for a record $$ 3 million. The buyer was later revealed to be Todd McFarlane, who said he had spent all of his life savings on the ball. Sales were more than 23 times the value of any baseball before 1999.
$ 3 million in savings is a lot of money to spend on just one ball, but Todd's love of the game was obviously strong enough to overrule logic. On the other hand, if the ball has increased in value since then, it might be a smart investment. Only time will tell.