I posted a while ago about how I felt that developing in text files is such a bad idea. That code should be a structure in memory. This would enable features like: being able to instantly evaluate tests as you change the code. The ultimate in timely feedback.
Well I just came across this project today, which is getting a long way towards the future I predict.
Check out the movie demo..
Then imagine duplicating the state each time you set up a test so you can see all tests in your state at the same time. I'd love to try TDD with this tool.