We have some old virtual machines with VS.NET 2008 installed, used to build and maintain packages for WSS3 / MOSS 2007.  Now that we have a nice new TFS 2010 installed, I go about fixing them up and making sure the various projects lying around are properly checked into TFS.

Getting an unpatched VS.NET 2008 to talk to TFS 2010 involves:

1. Installing VS.NET 2008 Team Explorer - this allow VS.NET 2008 to be able to talk to TFS as a source control system.
   http://www.microsoft.com/downloads/en/confirmation.aspx?FamilyID=0ed12659-3d41-4420-bbb0-a46e51bfca86&displaylang=en
   
2. Installing VS.NET 2008 Service Pack 1
   http://www.microsoft.com/downloads/en/details.aspx?FamilyID=27673C47-B3B5-4C67-BD99-84E525B5CE61
   
3. Installing VS.NET 2008 Forward Compatibility Update for TFS 2010

I fumbled around with the order a bit - was doing #2 before I realized I don't even have team explorer.  After I worked out what needed to be done, the order makes more sense.