Basecamp

Features :

A newsroom is a section to share news and messages. It works like a discussion forum, with a message topic and then content and replies. It also includes a section on the right side of the page, with a list of closes upcoming events from the calendar.
Pages are probably the key functionality of the whole application. You can create an informational page about various events or topics. It allows you to combine notes, files, pictures, and to-do lists, and creating this page is very simple. This tool would be useful for planning events, business trips, preparing presentations, or just providing general information about specific topics. The possibility to upload files and comments is available here as well. The pages could be private, visible just for specified users, or publicly visible for all users of the system.
The calendar offers the standard functions you expect from it. It is similar to Google calendar.
The reminders section allows you to add tasks, you want to be reminded about, either by email or text message. You can also set a reminder to another person.
Journal is a section where each member of a team can post a status about what he is working on at the moment. Then there is a wall where you can see all status updates from your colleagues. It works exactly like statuses on Facebook, however, you only see status updates on the wall, no photos are involved. This feature could be useful for a team leader who wants to know, what exactly are his team members working on at every moment.
Whiteboards are text documents that could be used for sharing information or writing documents in a group. Users can also add comments and the versioning system allows them to roll back or see who made which change. The difference between Whiteboards and Pages is in its format - Whiteboards contain just simple textual information, while Pages combine pictures, lists, files.