Thinking of offering credit cards?

If you are a small business and you are thinking of offering credit cards as a method of payment for your clients, then think about taking the PCI Security Standards’ self-assessment. Once you take the quiz, you will be in a better place to actually make a sound decision on the type of credit card solution you need.

Options:
http://www.authorize.net/
http://cashnet.com
http://paypal.com
http://paybycheck.com

Does anyone have any other recommendations for online credit card solutions?