Is it possible to create 'invisible' project using Visual Studio addin?

I have an idea to create some sort of extended Immediate Window VS plugin. I've noticed that when I want to test something (like new Regex or DB reqest) I tend to create new console app for this. The idea is to create project that is not included in solution and references current project and has all using 开发者_StackOverflow中文版directives from current file. So I'll have all advantages of code editor: usings (no full class names), syntax highliting, IntelliSense, multiline commands, other plugins (R#/CR).

Is this possible?

Option A: Write those in a test-project added to your solution

Option B: Create a console application added to your solution

Create a build-script that only builds the projects you want to give to your customers.

To gain some ideas: look at http://mvcstarter.codeplex.com/ (point 9)