Today in my Foundations of English for New Media course we are talking about Wiki's and we'll look at how to create one as a way to share work.
Google documents are another way to share, and there are many others you can use, sharing Dropbox files, for example.
But the real kicker with wikis is how they keep track of all the edits on the pages and who edits them.
There are plenty of wiki providers out there, free and easy to use. There's a list here: Tech&Learning.