Finding compilation error for aspx files
Some time ago I did a bigger refactoring in many of our *.aspx files. The big problem was not the refactoring itself but to find all small typos and similar. If you make a typo or a syntax error in a *.cs file you will get a compilation error when building the application, but that is not the case for *.aspx files. So to increase confidence of my work I decided to use the aspnet_compiler that is used to pre compile a site for performance reasons. It was so successful that we decided to add it to our build infrastructure to catch all of this errors early.
Example (just replace the C:\apps\MySite to your output directory when building your site/app.
C:\Program Files (x86)\Microsoft Visual Studio 11.0>aspnet_compiler -p C:\apps\MySite -v /