If you are lucky enough and have the privilege to develop on a Linux based environment, this little tip might boost-up your TDD process (at least the Unit Testing part). Please note, that this should work just fine with Apple computers also, but not tested!
With the following shell command you can automatically check your test results in every 15 seconds! (under protected/tests)
watch -n 15 -d phpunit unit/
My DEV screen looks something like this (Tests are running on the top-left!)
ps: of course you can change the time (in seconds) to whatever you'd like ;)