eCommerce Alternatives for Credit Card Processing?

A non-Anonymous Coward asks: "More and more these days, small businesses are selling their goods on the Internet, and are looking for a way to process their sales. Aside from purchasing a merchant account, and setting up systems that meet the requirements set forth by the payment processors, what alternatives do small business owners have? There are a few online companies that will process the money for you, and take a small portion of that, such as PayPal, authorize.net, 2checkout.com, and a few others, but what is the easiest to setup, with little hassle?"