Brits have at least 35 million old mobile phones lurking unused in the back of drawers. They also have 11 million old digital cameras, 9 million redundant PCs, 5.5 million old laptops, just over a million unused satnavs and 12 million outdated games consoles. And Asda wants to convert all of that unwanted technology into cold hard cash.

The UK retailer commissioned a national Omnibus poll which discovered that UK households are hoarding old gadgetry and gizmos worth £billions in trade-in value, so has opened a new Tech Trade-in section of its website, which offers money for old mobile phones, digital cameras, satnavs, MP3 players and handheld games consoles. Also, from June, Asda stores nationwide will join in the fun and the service will additionally accept laptops, PCs and larger consoles.

It is also offering a "Best price paid pledge to beat trade-ins elsewhere", although that's only when compared with direct rivals Envirofone, Mazuma, Sainsbury's, Tesco and Boots. You will get better trade-in value on a games console at specialist stores, such as Game.

For example, after a quick check, Pocket-lint has found out that Asda offers £16.01 for an old black Nintendo DSi, whereas Computer Exchange (cex.co.uk) offers £37 cash, £50 exchange for in-store credit.

Asda does, however, accept a whole range of old tech that you wouldn't be able to flog elsewhere, and you won't be able to exchange an old satnav for Coco Pops and a kilo of mince at a games store: “We reckon that the average UK home has hundreds of pounds worth of old gadgets that could be traded in for cash," says Phil Stout, Asda’s electronics service manager. "There are more mobile phones in the UK than people, for example, so there is a lot of cash out there waiting to be released. Our tech trade-in service means customers can now save even more on their gadget purchases at Asda or use the bounty to save on the cost of day-to-day living.”