Anachron - Offers companies the ability to provide their customers with online billing. - http://w3.anachron.com/
Verotel Billing Solutions - Offers third party credit card processing, 900 number billing and support for subscription-based sites. - http://www.verotel.com/
Rent to Pay - ACH and bankcard transactions for collection of monthly rents. - http://renttopay.com
Netbilling Processing Services - Provides Internet-based credit card processing for online merchants. Features include membership site management, a free shopping cart system and 24-hour customer service. - http://www.netbilling.com/