Cleaning out your closet or attic can reveal valuable items, whether sentimental or collectible. So what could an antique relic from your attic fetch at an auction or from an antique dealer?

Gobankingrates.com has compiled a listing of the top geeky collectibles that sometimes have more value than most people realizing and pack the potential for lucrative returns for their owners.

The list points to the fact that it's not just long-lost relics or rare antiques that can lead to a big payday. Sometimes, items from the recent past, including toys and other merchandise, can skyrocket in value for cultural reasons, for example.

"How much your geeky collectibles are worth can be subjective and might depend on a variety of factors like condition, rarity, age and demand," Gobankingrates.com says. "You’ll likely need multiple rare and valuable collectibles to fetch $1 million, but it could be worth giving it a try if you’ve got a collection."

These are the top geeky finds, in ascending order:

12. Sports Memorabilia

The value of some items in this marketplace are constantly changing, depending on how players and teams perform on the field. The Super Bowl victory by the Philadelphia Eagles this year, for example, drove up the price for a bobblehead doll quarterback Nick Foles by 900 percent, from about $30 to $300.

 

11. Toys

My Little Pony, Teddy Ruxpin and Strawberry Shortcake memorabilia are among the toys that have seen prices rise significantly. Remember Lite-Brite? The illuminated art board could go for $100 or more on eBay. 

 

10. Books

First editions are worth something if they are in good condition. According to Sotheby’s, a hardcover first edition of “Harry Potter and the Chamber of Secrets” is worth about $7,000.

 

9. Movie Collectibles

If a movie is a hit, all its associated promtional items and merchandise often soar in value. An original movie poster promoting the classic 1932 horror film "The Mummy," starring Boris Karloff, is expected to top $1 million at auction. Dorothy’s ruby red slippers from the movbie "The Wizard of Oz" are valued at between $2 million to $3 million.

 

8. Star Wars Collectibles

One movie in particular is off the charts when it comes to the value of spinoff items. CNN reported that one fan sold his collection of 600 “Star Wars” movie items for $505,202. A contest giveaway of a solid-gold LEGO mini-figure of C-3PO was listed at $10,000 on Gunaxin.

 

7. Trading Cards

Baseball card collections can be highly valuable. The Washington Post reported that seven Ty Cobb baseball cards discovered in the trash were worth about  $1 million. In 2016, Goldin Autions sold a 1909-11 Honus Wagner baseball card for $3.1 million.

 

6. Board Games

Smithsonian Magazine reported that a gold-plated Monopoly board and set cost more than $2 million. While you may not have a gold Mystery Date set to sell, some game sets may be worth $1,000 or more on eBay.

 

5. Action Figures

CBS news reported that a 1963 G.I. Joe sold for $200,000 in 2003.

 

4. Dolls

Whether it’s Cabbage Patch Kids or a vintage Barbie, dolls can be valuable as a collectible. The most valuable Barbie is the Stefani Canturi Barbie worth $302,500. A vintage Cabbage Patch Kids doll signed by its creator, Xavier Roberts, on eBay is listed at $9,700.

 

3. Stamps

The Postal Service issued its first postage stamp in 1847, and then later, the first commemorative stamp was issued in 1893. The ‘inverted Jenny’ stamp had a catalog value of $1.6 million, according to CNN Money, and was originally worth 24 cents.

 

2. Coins

This, along with stamps, is one of America's oldest collectible hobby, and still one of the most lucrative if you find the right coin. A doctor in Califonia stumbled upon his deceased parent’s coin collection hidden in a desk drawer, and it grew into a million-dollar collection.

 

1. Comic Books

How valuable is this collectible sector? Just ponder the river of tears shed by the countless baby boomers who never thought to save their childhood comic collections. The most expensive comic sold on eBay was a flawless copy of Action comics #1, with the first appearance ever of Superman, for $3.2 million in 2014.

The full report can be viewed here.