Photo credit: Stillfx

1. Spipra: Free online service allows you to leave comments on any page
2. HiTask: Project management tool lets you create and assign tasks to your team members
3. BitlBee: Free software allows you to connect to major IM services using an IRC client
4. Assembla: Get a free workspace with wiki, alerts, and chat for your team

1. Spipra
   
   Spipra is a free online service that anyone can use to leave comments on any web-page. It is really fast and easy to use: when you want to comment a page, just grab its URL, paste it in the box and click Go. You will be brought to a page where all the comments that have been made on that page will appear. If you want to comment back, you will need to register to the service for free by clicking here. Free.
   http://www.spipra.com/





2. HiTask
   
   HiTask is a simple web-based task management application that you can use together with your team. You can create tasks and projects, and assign them to your team just by dragging and dropping their name on the task. It also integrates a real-time chat, and you can export all of your activities in RSS format. Free to use.
   http://hitask.com/





3. BitlBee
   
   BitlBee is a free downloadable software that allows you to connect to major IM services using an IRC client. It's a great solution for people who have an IRC client running all the time and don't want to run an additional instant messaging client. BitlBee currently supports XMPP/Jabber (including Google Talk), MSN Messenger, Yahoo! Messenger, AIM and ICQ protocols, and is completely free to download and use.
   http://www.bitlbee.org/





4. Assembla
   
   Assembla is a free service that allows you to get free workspaces for your team, integrating tools like wiki, discussion, alerts, chat, and more. You can use use Assembla spaces for rapid software development, job networking, or simply online collaboration. Assembla is completely free to use for unlimited size teams, registration is needed.
   http://www.assembla.com/