I've recently visited an interesting website called musicMagpie.com, which offers to buy all of your unwanted CDs, DVDs, Blu-ray discs and games. "A very nice idea", was my first thought although after my initial admiration and further investigation, there are a few aspects that will not suit everyone.
To begin with Music Magpie's positive sides, I should mention that the process of selling your unwanted discs seems quite straightforward and easy. You enter the barcodes of your DVDs, Blu-rays, CDs, etc. and their evaluation engine gives an instant price for each of your items. If you are happy with the offered price, Music Magpie offers free shipping so you don't have to pay for anything by yourself. You can choose between UPS and USPS shipment and there are further options to select the exact shipping method. The payment is by check, which is good if you like checks. Another good possibility is to scan barcodes with your webcam instead of typing them. Finally, you can also download musicMagpie's free applications for Android or iPhone/iPad/iPod and turn your mobile device into a barcode scanner.
Independently of how good this service seems at first, there are several drawbacks that should be considered before getting too excited. To begin with, the service is currently available only in the United States. This is not a surprise having in mind the shipping costs for tangible products. Another issue could be the minimum number of discs you can sell. Due to the shipping costs, the minimum is 10 items per shipment. There is also a maximum number per a transaction but this is not an actual limitation.
What could be a drawback too is the paucity of payment methods. The only option is payment by check and although checks are fairly common in the US, not everyone likes them. Also, from what I've tried, it looks like recordable / rewritable discs are not accepted. And last but not least, the price musicMagpie offers for your Blu-ray discs, CDs and games is not very high. It should be treated more as a price for unwanted items rather than a price somebody who really wants your discs would pay.
So, to recapitulate, if you live in the USA, don't mind getting check payments and have at least a dozen of unwanted discs that just take valuable space in your home, musicMagpie could do you a favor. If this is not your case, services like eBay are probably a better option.