Credit Card Processors
Companies that offer you secure ways to accept credit card payments online for membership and/or services you offer on your sites. No merchant account is required. They normally charge higher commission, but are quick and easy to set up.
Online Check Processors
Services that will allow you to accept online checks as payment for your site for those who do not have a credit card. For a quite small fee, you can offer this alternative and sometimes more attractive option to your clients.
A very secure option for your users. They simply dial a 800/900 number to gain a password to your site or service, and get the fee charged on their phone bill.
Listings of companies who offer merchant account setup and/or services for adult site owners. They help process your transactions at quite low costs using your existing merchant account.