Our organization has roughly 100 applications (~50 ASP.NET, 30 ASP, 10 VB6, 10 other) , each application sees an average of 3 projects per year.  We are going ahead with VSTS/TFS and are planning out our use of TFS.

Given the limitation on TFS Team Projects (250 or 500), we can't simply have 1 Team Project for each IT project without supporting multiple TFS servers.  I doubt that will fly.

Should we have one Team Project for each application?  The work items are then shared - is it possible to distinguish between the work items for each IT project?  Will we really see performance problems (TFS Guide on CodePlex suggests that this technique could be problematic).

I also read on a blog that it was possible to maintain the source code in TFS but not for a specific Team Project.  Based on everything else I read this is incorrect - but I thought I'd check - anyone have info on this?

Any good resources for how to organize projects within TFS for an organization that focuses on development/maintenance of numerous small apps vs. development of commercial products?