I'm working on a very large ASP.NET solution that contains about 15 projects in it. In one of the projects - an Asynchronous HTTP Handler - typing has become a pain as it is very slow. I'm a fast typer - 115 wpm - and I end up typing a line of code and have to sit there and wait for the IDE to render those characters. I can't even switch to another window while this happens, or the rendering will simply stop. It's obviously extremely frustrating.

The IDE is slow in just this one project and nowhere else.

What should I look for that may offer a clue as to why it's being so slow?

(PS: C# codebehind)