Save hours each day - TD.NET
Until quite recently, my TD.NET usage had been quite conservative, I'd used it to run tests but had ignored all the surrounding features (why confuse things?).
The past few days I've gotten into using some of the more funky features TD.NET bundles with it's package such as the "Test with Coverage" and "Test with Debugger" options (which rock!).
If you're anything like me 90% of your work load is actually middle tier, converting database values into objects and visa versa, what better usage for a testing framework than to check if your middle tier is working as expected? You don't even need to write a UI to test the code is all working as expected meaning you don't have to rewrite the UI every time you change the business logic (cool beans!).
I suppose what I wanted to really say in this post is that if you're not using TD.NET or unit testing, give it a go, not to get into testing, but to get away from having to write and maintain UI's to "test" if your code works. With that, I'd be happy to bet I could rewrite most of my applications and the core of their code without any user interface what so ever - I'm that confidant with TD.NET and it's feature set.