If you are looking to pre-compile your web application projects with TFS 2008 Team Build, here are some tips.
First, you'll want to add the following to your TFSBuild.proj:
There a few things to note here. First, the Target Name is crucial; this Target will get executed after the drop is made, i.e. after the build successfully runs and your files are copied to the drop folder you specified when you created the build. Secondly, remember that this is running from the machine where your build agent runs. The AspNetCompiler MSBuild tag shown here will launch aspnet_compiler.exe on that build agent machine, and so "/Path_to_your_web" points to the virtual directory on the default web site of your build agent machine. Please note that "/Path_to_your_web" would be "/" in the case of your application being in the root directory. Finally, the Force parameter is required since we will be writing over the existing pre-compiled web on subsequent builds.
If you want setup a build agent on another machine, perhaps a development web server where you would prefer to deploy the pre-compiled web application, you'll need to configure that agent according to these instructions. This is a good idea when running verification tests that drive the web UI.