We use Foldershare for shared network folders and I agree, it works great except for Outlook. There is no reason that you can't take one of the files and also save it to Workspace but since there is no ability to organize files into folders we don't find it convenient to do so very often. We also use OneNote with Foldershare, which if you have never tried it, is one of the only really great user-friendly programs that Microsoft has ever produced. They must have bought it like they did Foldershare; they work great together and are both very easy to use.
We are using Workspace to share outlook items although I find it hard to understand why they can't have a normal looking calendar instead of that silly list. Things like project planning are very difficult without a calendar to look at. Workspace is shockingly primitive but you can link it to Outlook and its free, hopefully they will catch up with everyone else at some point.