I launched my first open source project in May of 2008. The link below is the main project page. If you are a drupal developer interested in contributing let me know. Alternatively, if you are interested in donating to this project or would like to sponsor development please let me know through the contact page.

http://drupal.org/project/role_subscription

This project was created with the thought in mind of giving developers and website maintainers an easy way to manage paid recurring subscriptions without relying on paypal necessarily which requires a paypal account and without having to rely on the common method of recurring invoicing.

We are developing this for 2 of our upcoming real estate web sites.