Look through this list carefully, because your old memories may be worth more than you'd ever imagine.
1. Boy Scouts memorabilia
The Boy Scouts of America have been teaching kids about citizenship and adventure for over a century. The Scouts have awarded millions of merits badges and medals — even a merit badge for "personal management" that teaches about saving, investing and credit cards.
Those who have held on to their patches and medallions have found those items can become very valuable. Large collections are worth the most.
Depending on age and condition, Boy Scouts merit badges and other trinkets can be worth over $1,000 — Scout's honor! One collection recently sold on eBay for over $1,300.
2. Irregular 2005 Kansas quarters
For 10 years starting in 1999, the U.S. Mint rolled out a series of special quarters celebrating each of the 50 states with iconic images. The reverse of the Florida quarter features a space shuttle and palm trees, New York's has the Statue of Liberty, and so on.
Nearly all the quarters are worth only face value — 25 cents — except for one coin with a significant goof. The 2005 Kansas quarter mistakenly was embossed "In God We Rust," instead of the U.S. motto, "In God We Trust."
These mishap coins can be worth considerably more than a quarter. A 2005 Kansas quarter in mint condition recently fetched nearly $50 on eBay.
3. Pokemon Charizard
Today's younger kids may know Pokemon primarily from the Pokemon Go fad of recent years. Slightly older pop culture connoisseurs more likely associate Pokemon with its long-running trading card game.
Some cards that have been around a while hold sentimental and collector value. But one is a veritable treasure.
A mint holo card of Charizard, a yellow dragon-like monster (above), routinely sells for thousands of dollars on eBay. Complete first edition Pokemon card sets can be worth even more, so get digging in that old toybox.
4. AOL CDs
If you survived the 1990s, you probably remember finding a promotional CD from America Online almost every time you went to your mailbox.
The original giant internet service provider spent an estimated $300 million to send out millions of trial discs in hopes of achieving home internet dominance. At one time, half of all CDs produced were for AOL, Smithsonian.com reports.
These throwaway items are now worth some cash to collectors, who want to get their hands on every color and design. Large AOL CD collections have reportedly sold for hundreds of dollars — enough to invest in that other kind of CDs (certificates of deposit).
Campaign memorabilia can be highly collectible. Former President Barack Obama's pins, coffee mugs, lawn signs, and bumper stickers have become valuable — and not necessarily from 2008 or 2012, when he ran for the highest office in the land.
Items from his earlier political career are even more popular with collectors.
On eBay, a lawn sign from Obama's 2004 U.S. Senate run from Illinois sold in January for $75, and a double-sided poster from the same campaign went for nearly $100.
6. Castlevania Super Nintendo game
Nintendo items are popular collectibles, but one game title in particular is an elusive treasure.
Castlevania is a gothic adventure game that pits a family of vampire hunters against Count Dracula. The game debuted in 1986, and the Super Nintendo version has sold on eBay in 2019 for more than $400.
Other editions, such as the PC and Sega versions, routinely bring $200 or more. The best prices are commanded by mint-quality specimens in their original boxes.
7. American Girl 'Samantha' doll
If your kids collected dolls over the past 20 years, you might have an American Girl or two in storage. They're still popular, and they're not cheap.
New American Girl dolls can retail for more than $100, and older ones can be worth quite a bit more, particularly if they had a limited production run or were discontinued.
The "Samantha doll" first came out in 1986, then was retired in 2008 — until a 2014 re-release. If you have one of the pre-2008 Samanthas, you might get hundreds of dollars for it. A 1986 Samantha doll sold on eBay in March 2019 for nearly $2,000.
8. Old cellphones
Most people don't hold on to their old cellphones but instead turn them into cash or trade them in for a smartphone upgrade.
While a used, recent iPhone or other popular phone can quickly turn into hundreds of dollars on eBay, Gazelle, Decluttr or other electronics sales sites, a phone from 10 years ago likely won't get you more than just a few bucks.
But stretch back to the birth of cellphones, and you'll find lots of treasures. A "brick" style mobile phone from the 1980s typically brings several hundred dollars, even in poor condition.
9. Magic: The Gathering card sets
Magic: The Gathering cards were introduced in 1993 to the delight of game nerds all over the globe.
A dog-eared pack of the cards isn't going to be worth much, but a sealed first edition — called the Alpha deck — can be worth thousands. Just a beat-up, empty Alpha deck box can get you $85.
The ultra-rare Black Lotus card is the treasure of the series, and one of them recently sold on eBay for $16,000. Yes, that was the price for one card!
10. Old Apple computers
Apple computers retain their value while other computer brands quickly become obsolete and worthless. If you have an old system, don't let go of it.
It's likely worth a few hundred dollars now, even just for parts. And if you wait a few years, the collector allure will increase.
An original Apple-1 computer from the 1970s sold at auction in 2018 for $375,000. A 1984 Macintosh can go for anywhere from hundreds, to more than $1,000.