ASP.NET TDD
I'm a big fan of Test Driven Development (TDD), but I've only used it on one project. Even then it wasn't strict TDD, but we did use NUnit to write a lot of tests.
(For those not familiar with TDD here's an overview - basically you write the test first, knowing it will fail, then code until it passes. Read this book.)
It's harder to incorporate TDD into an existing product of course - by definition you're too late! The Dozing Dogs CMS project was started back in 2001 before I'd even heard of NUnit, but even now I'd like to start adding tests to help with the stability of the code when making code changes.
My problem is that it's an ASP.NET application, not Windows Forms, and I'm not sure if it can work as effectively in this environment1.
I've taken a quick look at NUnitASP of course, and read some articles about it but that seems to concern itself with the UI which I don't remember ever needing that much testing.
For completeness on a new project it may be worth it, but writing tests to make sure your button clicks when you -umm- click on it? I don't remember that sort of thing ever breaking. I may be missing something.
In fact, the only time I used it, we wrote most of our tests for the class libraries; I don't think many were written for the front end or even the middle layer. And the problem with my ASP.NET class libraries is that a lot of them read/write the database and how can you do that in test mode? Perhaps you just use a test database connection string and populate that initially from the production database.
I'd be interested to hear how many people use TDD on ASP.NET applications.
1 Actually, it's not the environment per se, but the nature of ASP.NET web applications which generally seem to be more about the UI and less about doing work, don't you think?