Rentacoder.com was the first one I stumbled across, and I have since found Guru.com and Elance.com also.
These seem like a good idea at first glance. A marketplace where people can go to in order to contract your services. And who knows, some people may be able to create something like a steady income through these sites.
But for me, well I'm not too sure.
It smells like a market stall to me. Where brands are either non existent or weak, clients search on price, and there is no direct contact or sales process with the prospective clients.
When services like ours become commodities, which is what this is, then the only thing you can really compete on is price. Value goes out the window and high yield engagements are reduced. Particularly when you are now competing on the "level economic playing field" with people from countries like Pakistan and India.
(The Secret? Level playing field means lowest priced labor wins)
I'll stick with the old fashioned meet the clients type approach for a while I think. (But I will continue to buy cheap services there)