I spent time today playing with NextWorth, a Web site that will tell you the trade-in value of many electronic devices. The site covers everything from MP3 players to video games, but I went straight to cell phones, of course, to see how much I could round up for the handsets we have sitting around the CNET offices.

All you have to do is go to NextWorth's site and plug in the name of your device. You'll also have to answer a few questions such as if any parts of the handset are broken or water damaged, if it turns on, and if you happen to have the original box, battery, and user manual. You'll then get an estimate of how much your phone is worth. To get your payment, you can mail in your handset using a prepaid shipping label or take it to a participating Target store.

I took 10 cell phones that we've reviewed over the past two years and plugged them in. A couple very recent handsets, like the Motorola Brute i686 weren't listed, but I could find a match for most phones I tried. Not everything had a trade-in value, but I could get at least a couple of dollars for most devices. Here's what I found.

On the whole, I'd say that most offers were pretty fair, but I was expecting more for the Droid Pro and the BlackBerry. Also, I was surprised I couldn't get at least $5 for the MyTouch 3G. Still, NextWorth offers a good way for some consumers to get cash for their old devices. And considering how quickly some people switch cell phones, it's a great way to make sure your cell phone ends up being recycled rather than ending up in a landfill.