Well, I've taken the plunge and joined the other free-cyclers in my neighborhood and I have to say what a great way to both get rid of something you don't use and also try to find something you truly will use all without spending a cent. I lurked on the message boards for a few weeks before trying to decide what it was I wanted to ask for (a battery operated pump for my balance ball-still no offers though) but after seeing a WANTED post for a Roomba and realizing mine was just sitting in the utility closet collecting dust, I figured why not pass it on to someone who could appreciate it. Most freecyclers arrange time and place to make their exchanges, but the cheapest and easiest way for all parties I figured was to just leave the item on the porch and the WANTER could just pick it up at their convenience. No fuss, no muss. And no hard feelings if or when the item breaks because it's all for the low low price of FREE! And even better there's no obligation—say you really need a new blender, what do you have to lose by posting a request? If you find one, you've saved yourself the money (and the manufacture of a new product), if you don't find one, you're no worse for trying. To find a group in your area: www.freecycle.org
And Freecycle's not the only place Care2 ran a list of 5 other online free or trade sites.