Unfortunately - yes. I think you're asking for the cake, the cake PAN, and the cake knife, all of which would have to be edible:)
Reporting services is not the place for that. You're looking for some (ASP).NET app, to pull in data, update it and use the updated date in a further report (which would be implicitly read only or disconnected from the original source). VS2005/2008 would help you whip something like that up pretty quickly.
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Your lack of planning does not constitute an emergency on my part...unless you're my manager...or a director and above...or a really loud-spoken end-user..All right - what was my emergency again?