Get a Second Shot for Free!
On September 15th, we will be launching Microsoft's Second Shot offer! Get a free retake on your next Microsoft IT Professional, Developer, or Microsoft Dynamics certification exam.
This is a limited offer so plan now! If you register for the Second Shot offer starting September 15, 2007, prior to taking any exam, you will receive a free Second Shot exam if you don't pass on your first try.
For more info see here & here.
It looks like this is only for Prometric, though