phpBMS is a Web-based billing, scheduling, and
client management system. Its features include PDF
generation for printing, mass emailing to clients,
repeatable task and event handling, and
quote/order/invoice tracking.
Information regarding Project Releases and Project Resources. Note that the information here is a quote from Freecode.com page, and the downloads themselves may not be hosted on OSDN.
The package has undergone many bugfixes and several enhancements, including the ability to attach external files to product, client, or invoice records. The package can be installed over the top of existing installations (using the update script) and upgraded without losing data.