If you have not tried OLW, check it out.  I started using this for a cross Edu project and it works great.  Think MOSS "lite" that works awesome outside the firewall out of the box.

 

Group projects are tough when everyone has different schedules. One way to stay organized is Office Live Workspace. Your group can store and access files and calendars in one place, plus share notes, school work, and more. Join the more than 1 million customers already using it!

 

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