Before I got a merchant account, I used http://www.ccnow.com
-- not too cheap, but they maintain the shopping cart, ssl, and you use their merchant account. That was before PayPal was set up with a cart. You have to sell physical merchandise, and like most things like this you can't do things like give partial refunds, add things to orders, or take phone/fax orders.
They were really easy to work with and it got us over the hump to where we got our own merchant account. I use a custom-written PHP shopping cart that we wrote up in a Web Techniques article and process my cards manually which works for me.