An unopened first-generation iPhone from 2007 went up for auction andwas sellingfor more than $16,000 on Thursday.

Experts say there’s a growing market for vintage electronics as collectible items.

“Gadgets are things we use every day and oftentimes all day for a period of our lives.

A vintage Sony Walkman with matching headphones against an orange background.

Florian Schmetz / Unsplash

The phone sports a 3.5-inch screen, a 2-megapixel camera, and a whopping 8 GB storage.

you’re free to’t even add apps.

But it’s not the specs that drive up the prices of old electronics.

Several vintage cameras and accessories arranged on a table with a plant, books, and modern headphones.

Cavan Images / Getty Images

The availability of online marketplaces, such as eBay, has made it easier to find such buyers.”

Consider looking in your attic for old electronics, as certain rare items have sold for big bucks.

Also valuable is the Zelda Minish Cap Game Boy Advance, which went for $24,000.

Some ultra-rare gizmos can reach stratospheric heights at auction.

Last year, a functionalApple-1 computer hand-numbered by Steve Jobssold for $468,750.

Cavan Images / Getty Images

Diminishing Returns

Not all gadgets gain value as they age.

One study analyzed the originalretail prices of 22 popularly re-sold itemsagainst sold prices on eBay.

Cell phones lose 42.7 percent of their value in a year and 79.96 percent within five years.

Former professional hackerNick Donarskihas a closet full of old gadgets he tinkers with.