Redmine - Flexible project management web application
Asana - Asana project management is an effort to re-imagine how we work together, through modern productivity software. Fast and versatile, Asana helps individuals and groups get more done.
Zenkit - Zenkit is the home you always wanted for your ideas, your projects, your business.
Teamgantt - Intuitive project planning and collaboration. Beautiful Gantt charts, task-level communication, file sharing, resource management and more.
Taiga.io - An Agile, Open Source, Free Project Management System
Basecamp - A simple and elegant project management system.