As you know, normally Visual Studio 2008 does not let you open *.csproj files from the current solution in the editor (for example, when you want to tweak the build process to compile these custom DSL scripts of yours). I used to resort to starting second instance of VS just for the XML editing with the IntelliSense.
However, as it turns out, there is another approach:
- Right-click on the project in "Solution Explorer" and select "Unload Project".
- Right-click on the project again and pick "Edit [ProjectName]".
- When you're done with the editing, just hit "Reload Project".