After trying to sort out the best way to facilitate asynchronous communication for a group project, I was reminded of P2. This talk by Pete Davies at WordCamp SF this past year tells a very compelling story about why you should use P2 on your project. You can use it for free on WordPress.com or download it to run on hosted WordPress. It took all of a few minutes to sign up for a free WordPress.com site and switch to the P2 theme. After that it was all work.