For an easy way to trade-in old tech gear, it's hard to beat online services that offer cash or store credit for your unused phones, PCs, music players, video games, and DVDs. A variety of big-name sites, including Best Buy, eBay, and Gazelle, accept trade-ins.

Amazon does too, of course, but until now its Trade-In Store accepted goods in just four categories: Books, video games, movies & TV, and electronics. But there's good news for those of us with dusty stacks of audio CDs: Amazon will now take your discs as well.

The service is currently available on Amazon's US website and you can login with your account there and be paid in USD, but Amazon UK have yet to confirm when they will have the function.

On the US website, to submit a CD in exchange for an Amazon gift card, go to the retailer's Trade-In site, select the "Music" category, and enter the artist and/or album name you'd like to trade.

In my test, Amazon offered $4.50 for a two-disc "Marvin Gaye Anthology" in "good" shape, or $4.95 for an "Anthology" set in "like new" condition.

I could try to sell my CDs individually, but it's not worth the time or trouble. It's easier to print a UPS mailing label supplied by Amazon (shipping is free), stuff my CDs in a box, and send them off.

There's one caveat, though: After examining my CDs, Amazon may decide they're worth less than the agreed-upon price, in which case they'll return them to me at no charge. (When you first accept Amazon's offer, you can decide whether to accept a lower price if Amazon deems your trade-in to be worth less, or just have the item(s) returned to you.)

If you have old CDs you'd like to unload, give Amazon's Trade-in Store a try.