<p>I have a web application that is becoming rather large. I want to separate it into smaller more logical projects, but the smaller projects are still going to need to access some of the classes in the app_code of the main project. What are some good methods to accomplish this?</p>

Add a class library project with the common classes and add a reference to this project to each of the new projects.
So you'll have the following Solution layout
```
```
/webapp1
   /default.aspx
   /....
/webapp2
   /default.aspx
   /....
/lib
   /Utils.cs
```
```