I recently learned about Gazelle, a service that will buyback a wide variety of used gadgets. The website works like a "reverse" Amazon.com. You search for electronics that you own and want to get rid of. For each, you are asked a few questions to rate its condition, then add it to your "box". You are given an offer for each item.
Depending on the total value, they may send you a box or you can use your own. Gazelle provides a ship-back label that you tape to the box. Once received, they check the gadgets out, ensure everything matches the condition you specified, and then pay you. They offer payment in multiple forms, including PayPal, Amazon gift card, and check by mail. For items with no resale value, Gazelle will recycle it in an environmentally responsible manner for free.
Overall, the process is pretty easy although I ran into a few snags. On my first order, I chose Amazon.com gift card as my reimbursement method, but the gift certificates never arrived via email. After a few contacts via their online customer service chat, the agent was able to manually email me the claim code. On my second order, I returned a working iPhone 3G. Their inspection indicated they couldn't make a call with it. This lowered their offer price and my choice was to accept the lower offer or they would return in.
Again, I contacted their customer service via online chat and indicated the phone was working and requested a second check. The rep indicated it was unlikely the decision would be changed but requested re-inspection - and as it turned out, the SIM card they used for testing was not activated properly. They restored the original offer price. It took a little over a week for the check to reach my mailbox in this case.
Despite a few minor snags, I'm pretty pleased with the service. As the service grows, I hope they clean up the process a bit but in the meantime they offer a good alternative to old gadgets collecting dust in the closet.