Thanks Craig and Josh. Yes, the session object in service pack three is exactly what I need.

>>It is trivial to create a single form with multiple tabbed pages. (you have to watch the refreshes but that seems to be only gotcha.)
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>Look at the LockScreen property of the form.

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>>What I cannot find a way is to create a true tabbed application -- each tab having it's own separate private data session.
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>Service Pack 3, which was released yesterday, has a new session object that may be of some help for you.