PBwiki

As you probably know business school is all about group projects. Given that I've done a fair amount of research on Web 2.0 topics I figured I should put my money where my mouth is. I've been using PBwiki for many of my class projects. I haven't tried many of the competing products but PBwiki was easier to uses the the other ones I checked out. One of the features that I like is that you can set it up to email you when there are changes to the page. This means that you don't have to constantly check to see if your group members have made changes. In addition, they are offering ad-free wikis for educational purposes.

The company has been adding features since their recent round of fundraising.

I'd love to hear what other collaboration tools you have been using. The field of solutions seems to be growing more crowded everyday.