Do you remember the epic fail that bricked the Zune a whole day on the last day of last year, a bisextile year? I described here and here how this error could have been entirely avoided using basic unit testing.
You probably remember (if you read the original post) that I first claimed that it’d take a few seconds to check all possible dates but in fact it ended up taking something like 90 minutes. This week, I come back on unit testing of a very large domain under a time constraint.