kalantir wrote:
So nobody wants to have a go at my riddle?

Um... you need to ask the same question to the three guardians, one you know the answer to. Two answer one way, one answers differently. Then you ask the different guardian, "is this the door to wealth beyond measure?" about two doors.
And if the question you asked had a true answer and the Guardian answers the same to one door, go through that one. And if the guardian answers negatively to both doors, go through the last one.
_________________
"There's no sense crying over every mistake,
you just keep on trying 'till you run out of cake."
-Still Alive, ending song to Portal