If you are looking for a way to test or run the Visual Studio Team System 2008 Database Edition GDR release inside a virtual environment, you can download one of the following two VPC's. There is a Virtual PC and Hyper-V based image. Both images include a full Visual Studio Team System 2008 Team Suite installation and a TFS server installation.
For details check out Brian Randell his blog covering this announcement.
You can download the VPC from the following location:
Note that the Virtual PC version requires that you are using the latest Virtual PC 2007 SP1 installation.