I know this is not a new concept but I had never seen this site before. I was recommended to go to it by my local Red Cross to donate my cellphone. I actually had a few very old cellphones lying around that I donated to charity through FlipSwap.
They offer you a trade-in price which is significantly less that what you would get on eBay but it is pretty decent considering that they pay for shipping. They even accept your old worthless phones which they recycle. (Or send to 3rd world countries)
For example the trade-in value is relatively decent on some phones
8110 – $107.71
8320 – $177.29
8820 – $164.63
They are even offering to take your BlackBerry 9000 off your hands for @281.64
Its worth checking out if you are too lazy to put your old Berry on Craigslist or eBay. Just head to www.flipswap.com