In my recent "Utilities you didn't know you had" podcast, I realize now I totally forgot about REG.EXE.

I was reminded while browsing James Manning's blog

From CMD.EXE, this tells you where VS.NET 2005 is installed:

C:\>reg query HKLM\SOFTWARE\Microsoft\VisualStudio\8.0\Setup\VS /v EnvironmentDirectory

Here's the same thing in MSH (gp is the alias for get-property):

MSH C:\>$(gp HKLM:\Software\Microsoft\VisualStudio\8.0\Setup\VS).EnvironmentDirectory