Don’t just roll with Google Docs without some due diligence research. I’ll make it easy and start the research and provide some links below.

Lots of tools out there with extra features so figure out what works best for you, your team and business. These will have a place in a personal setting too for some people.
1. Zoho Viewer: Upload, view, and edit documents online, and get feedback from your team

2. Wetpaint: Create free wikis and invite people to collaborate with you

3. Project Office: Manage projects, assign tasks, and create wikis to collaborate with others

4. SproutLiner: Create to-do lists and use to them to manage projects with your team

5. Digsby: Combine multi-protocol IM, email and social networking into one application
Read more about Digsby here, its quite cool

6. Weblin: Browser add-in allows you to chat in real-time with the people browsing your same web-page

7. TwitterShare: Share any file up to 10MB as a Twitter post

8. Wizlite: Highlight text on any web-page, and let other people see and modify it