There is an awesome tool for building more complex JavaScript applications called IntelliJIDEA. It was originally built for Java development, but I have personally used it on a Twitter AJAX app that we built for my company. It can refactor your JavaScript and help you write a lot smarter code. It may be overkill for what you are looking for, but it is still a great product.

www.jetbrains.com

They have both an Ultimate (commercial) and Community (free) edition of their software.

Yes, your eyes, and hours reading code (: