qdPM is an open source project management application that is created for small teams in mind.
It is built with PHP/MySQL & relies on Symfony Framework (bundled with the download package).

It has support for adding extra fields for projects, tasks & users which eases customizing the application.
With the multiple task editing feature, it is possible to work with multiple tasks faster.
Projects in qdPM can be set to different billing types like per hour, fixed price, etc. & a powerful reports module helps analyzing these data like any other data in the system.
The application is multilangual & already comes with various language files.
Requirements: PHP 5.2.4+, MySQL 5+
siwapp is an open source web application, built with PHP (Symfony), that enables anyone to create & manage invoices with ease.
The application has a slick interface & provides a simple usage to create professional-looking invoices.

Some features of siwapp:
- invoices with different serial numbers can be managed
- invoices can be downloaded as PDF files
- periodical invoices can be created automatically
- & more
siwapp uses MySQL to store data & if you need periodical invoices to be e-mailed automatically, a scheduling system (like cron) must be used.
It can also work as a module (be integrated to other business management applications) with the API support.
Requirements: PHP 5.2+, MySQL