6. 1993 Magic: The Gathering Alpha Black Lotus card
Sale price on eBay: $27,302
This is a diamond in a card-game world with a whole lot of rough.
The downside to being a casual Magic, Pokemon, Yu Gi Oh or other card collector is that it's really tough to find one of any value. As the games became more popular, sets went into mass production and the market was flooded with just about every iteration imaginable.
But Magic creators Wizards Of The Coast planned ahead. After Magic debuted in 1993, the company began compiling a "reserve list" of cards they vowed never to reprint. The list covers a select number of cards made from 1993 through 1999, including a particularly valuable group known as the "Power Nine."
Those cards were available only in three sets printed from 1993 through 1994. They're so powerful in the context of the game that they've been either restricted in tournament play or banned from tournaments outright. The Black Lotus, in particular, is considered extremely powerful for its ability to shift a game's balance of power quickly in the early stages.
Some players absolutely love it, some loathe it, but the Black Lotus itself is so revered that enlarged versions with specialized art are handed out as tournament trophies. There were little more than 4,000 produced in total and only 1,000 produced as part of the Alpha series. Considering the amount of time passed, attics cleaned out and yard sales held since the Black Lotus' debut, many of those have been roughed up or disposed of altogether.
If you find yourself at an auction with a reasonably preserved version of this card staring you in the face, play it cool and hope it hasn't made its way online.