For my class set up this year I have decided to use a combination of a "home" blog (using Blogger), and then linked wikis for each class. The home blog can have frequent general messages to students and parents about what's going on with the 1to1 laptops, and maybe some general info about my classes and expectations. That's where I also post the links to my class wikis in the sidebars. Over time, I'll add more widgets to the sidebar but for right now I'll start slow so that the kids and their parents can get used to the idea.
I've set up some simple wikis using Wikispaces for each class. Again, I'm taking this in baby steps - I haven't invited the kids to be "members" of the wikis yet - they are basically being used as web pages right now as I continue to add content. The kids simply go to those places for some class links, info, and assignments. The only pages I've added to those are a calendar page (Google Calendar), page for our current unit of study that has links, news, and assignments, and on some of them just some extra activity pages.
I foresee these becoming more dynamic and interactive as time goes on, but for now we'll just do one or two things at a time.
If you are interested in checking out what I've done so far, go to my class home blog and click the links on the right to see the classes. When you get to the class wikis, the menus are on the left to see other things besides the class home page.
I'd be interested to hear about other types of set-ups people are using for their classes with free open source stuff like Google and Wikispaces.