Beyond P=NP: this actually gives you a constant-time solution for any problem where it's possible to enumerate candidate solutions, regardless of how long it takes to do so. So, we'd have ANYTHING=O(1).
Only if you are certain there is a correct answer. If there isn't a correct answer, you just cause a paradox. It's also more likely that the machine will spontaneously fail, or the creator will get hit by a bus before he can complete it, etc.
