Skipping post-build in VS project in Team Build

Interesting question has come up in the forums: "If one has custom pre- or post- build logic in Visual Studio projects, that are being built both on desktop and using Team Build, how one would disable the pre-/post-build for non-desktop build?".
Or to be more concise - is there any property available that makes it possible to detect, whether the build is being performed from Visual Studio or from Team Build process?

Now, Team Build build types will simply call MSBuild task with the solution(s) to build; will Team Build pass any custom properties to MSBuild with the solution files?

It turns out that Team Build does indeed pass such property, named TeamBuildConstants; thus when the solution will be built from the Team Build script, the property will get the value of _TEAM_BUILD_, as defined in Microsoft.TeamFoundation.Build.targets file.

Then Visual Studio project (C# and VB.NET alike) can be modified in the following manner:

<!-- Prebuild logic will be executed both in VS and Team Build compilations -->
<Target Name="BeforeBuild">
    <Exec Command="attrib -r $(TargetPath)"/>
</Target>

<!-- Postbuild logic that will not be executed in Team Build-->
<Target Name="AfterBuild" Condition="'$(TeamBuildConstants)' == ''">
    <Copy SourceFiles="$(TargetPath)" 
      DestinationFolder="$(SolutionDir)\bin\$(ConfigurationName)" />
</Target>

Team Build targets file also exposes property with very tempting name - SkipPostBuild; however, modifying the property value in TFSBuild.proj will have no effect on the projects post build logic. Setting SkipPostBuild property to false disables running GenCheckinNotesUpdateWorkItems task during Team Build build, and thus has no connection to Visual Studio projects logic.