Group and Project Work

Tool name
A free website that facilitates online group and project work - communication, filesharing etc.
Very popular platform with the basic collaboration functionalities you might need. However the free version does not include file sharing.
Basecamp integrates Campfire for chat-meeting room (with chat history). However the free account only allows 4 users and limited storage.
Consider using Basecamp together with Dropbox for 2 GB free file sharing sharing, and together with Messenger for free chat functionality (enable chat history to save your chats)
Free version without filesharing/storage.
Payment options
Free and easy to use group collaboration tool, complete with shared calendar, meeting scheduling, chat, shared file space, polling, messaging in various ways etc. It does not provide shared to-do list or milestones list, but has a good calendar function which can be used instead.
Good intuitive tool with all the functionalities needed for online collaboration; document sharing, shared to-do lists, wiki functionality, etc. Unfortunately, the number of users allowed and the available document storage space in the free version is not enough to make it a really useful tool (see right column). Consider using it with Dropbox for 2 GB of free storage.
Free (up to 2 projects, 25Mb of document storage space, and up to 5 users per group)
Payment version
A very comprehensive collaboration tool, which is free to use for up to 50 people. It is actually a free hosted wiki, with profile spaces, personalised dashboard, wiki, and blog functionality, micro-blogging functionality, as well as a desktop application, which can sync your content with your computer.
Free up to 50 people
Payment options
This is a system developed in Germany and traditionally used by many universities. It has all the basic functionalities that you need for virtual collaboration and it is free. You can install your own version if you have access to server space, or you can use the hosted online version.
The interface is a little altmodish and the functionalities are not exactly intuitive/user-friendly, but once you get the hang of it, it does the job.
Nice collaboration environment, complete with wiki and blog functionalities, group/network management, project management tools, etc. Unfortunately, the free version allows too little upload space to be really useful. Consider using it with Dropbox for 2 GB of free storage.
Free version; unlimited work-spaces and users, 250 Mb free personal storage, 10Mb file size upload limit, Sosius interface skin only, Adds.
Payment options
Verb is a very simple and free tool, which basically allows you to share a to-do list and send messages to groups of up to 10 people. It only has this limited functionality, but it has a cool and simple interface and seems to be very stable.
Google Wave
Google has announced that it will close down the service
Google Groups
Google groups allow you to have a shared working-space for your group work. The group will contain group-member-profiles, a common repository for shared files, a discussion forum, etc. You can choose how often the system should update you on changes applied to the group by the other group members.
In its current form, google groups has not been updated for a while, and it is not particularly recommended for group work. The main shortcoming of the system is the lack of a functionality, which would make you able to sort your files into sub-folders. Another huge obstacle is the missing overview of new changes to the site, and a very messy discussion forum. All in all this makes the groups difficult to use.
Project management tool. Manymoon is a social productivity application that makes it simple to securely share information. By using Manymoon you can avoid the chaos of email and better communicate with the people you work with.
You can use it to manage tasks, post interesting links, work on projects, share documents, find out what other people are working on and simplify communications with co-workers, customers and partners.
There are premium versions of Manymoon available that require a monthly subscription.
Project mangement tool. See video.

Project management tool.