Trello vs. Redmine vs. Taskulu

Trello is a collaboration tool that organizes your projects into boards. In one glance, Trello tells you what's being worked on, who's working on what, and where something is in a process.

Redmine is a flexible project management web application. Written using the Ruby on Rails framework, it is cross-platform and cross-database.

Taskulu is a collaborative project planning service. It combines task management, real-time chat and time tracking into a single interface.