Collabtive is an open source project manager that can be placed on your server. This project manager allows you to create projects, timelines, schedules, add/remove teammates, and adds a progress bar. Teammates can message each other about the project they are assigned and also upload files to the database. Installing is easy with Linux and MySQL and starting is a matter of creating an Admin account.

Here is the complete list taken from the site (http://collabtive.o-dyn.de/about.php):

Core functionality

• Unlimited projects, milestones, tasklists, and tasks
• Unlimited members with user profiles
• Role-based permission management
• Messaging and instant messaging
• File management
• Timetracking

Reporting and notifications

• Timetracker reports, activity logs and messages in PDF format
• Export user profiles as vCard
• RSS feeds for messages and tasks
• Synchronization of calendars via iCal task export
• Excel files from activity logs and timetracker reports
• E-mail notifications

Other

• Search, tags
• Basecamp import
• Fully themeable
• Available in more than 25 languages
• Full UTF8 support

Let me know what you think of this program! I love it and makes project management easy.