If you've got a garage that's full of outdated technology, it could be a bit of a treasure trove. The Commodore 64 was a hugely successful computer model in the 1980s and 17 million units were sold when it debuted. The old computer originally had an RRP of $595, the equivalent of $1,800 (£1,390) in today's money, and can now be found on eBay going for up to $1,200 (£930).
Is gaming more your thing? Consoles such as the Nintendo Game Boy Color, which was released in 1998, are also being snapped up online. The Australian Ozzie! Ozzie! Ozzie! version is particularly valuable, with one recently having sold on eBay for $708 (£550).