You might not think your failing Nexus 6 is worth much - and to be honest, it isn't really. On the other hand, certain bits of tech memorabilia have been known to fetch very high prices indeed, and here we're going to round up some of the most notable vintage tech auctions.
The key to finding hardware that's going to grow, and grow, and grow in value is to find devices that have a place in tech history for some reason. Admittedly that's not usually easy to do at the time they go on sale, but if you get it right the cash rewards can be huge.
1. Leica O-Series
You might balk at some of the prices thrown around for the digital cameras of today, but they're nothing compared to the price of the vintage Leica O-Series camera, one of the first ever 35mm models in the world - of the 25 shooters made in 1923, there are 12 left, and the most recent one to be put up at auction fetched a cool $2.79 million (about £2.1 million).
According to the camera auction experts, these specific O-Series models are appreciating value like crazy, so its probably worth having a rummage around your attic room to see if you've got any classic cameras gathering dust upstairs. As for the camera itself, it was actually a prototype for the Leica I (Model A), hence it fetching a high price for its rarity.
2. Apple Lisa-1
Apple always attracts interest from tech enthusiasts and collectors because of the reputation of its brand and the quality of the goods it puts out: it's one of the most iconic companies in tech. That said, with tens of millions of iPhone 7 handsets sold, that device is unlikely to start gaining in value any time soon - it has to be something classic and rare.
Enter the Apple Lisa-1 computer, which just a few years ago attracted a price of $44,000 (about £33,260) at auction. Why so high? Not because of its processing power or sleek looks, but because forerunner of the original Mac is one of the very first computers to have a mouse and a graphical user interface (GUI), setting the modern-day computing template.
3. Xerox Alto
Speaking of classic computers, the Xerox Alto is another machine that attracts very decent prices indeed whenever it goes up for auction, most recently $30,100 (£22,730) for one that doesn't even work any more - as with any auction of vintage tech, if the gadget actually works and is in pristine condition then the price can potentially go up much, much higher.
For those of you who weren't around in 1973, the Xerox Alto was similar to the Apple Lisa-1 in that it was one of the first machines to adopt the graphical user interface (GUI) approach to computing rather than the traditional command line approach. Only around 2,000 of these computers were ever built, which is why they can command such high prices.
4. Apple I
We've already mentioned the Apple Lisa-1, but go further back in time to something even rarer and you get prices that are even higher. The Apple I computer was hand-built by Steve Wozniak (in Steve Jobs' garage, so the story goes) and dates from 1976, making it hugely collectable and desirable for the wealthiest and most loyal Apple fans out there.
The latest Apple I we've seen go up for auction pulled in a rather impressive $671,400 (£507,440) after bidding, making it the most expensive Apple computer in history (that iMac doesn't seem so pricey now). While no one knows for sure, it's thought there are less than 50 Apple I computers in existence, making it the ultimate tech collectable.
5. Nintendo World Championships cartridge
It's not just computers that can fetch vastly inflated prices at auctions - there's also a growing and lucrative market for vintage video games, particularly those released in limited numbers, or made for systems that didn't last a very long time. If these game discs or cartridges come in sealed packaging and have never been used, so much the better.
As evidence we present to you a Nintendo World Championships cartridge for the classic NES system, which was auctioned off online and was bought for $100,088 (£75,525). What makes this game particularly collectable is that just a handful of the cartridges were ever made, released as a promotional offer on the front cover of Nintendo Power Magazine.
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