Although I've seen and written amusing error messages my personal favorite was an entire enterprise application that never threw a single error, EVER.
in reply to Useless/Interesting Error Messages
It was an Oracle Forms application and part of the spec requried all excepetions to be "handled." The spec was sent out of shop. Naturally, the initial code was stubbed out with place holders for all the exception handling code.
Unfortunatly, as often happens, time ran short and dead lines loomed. The code "ran" so was returned to us, where it "passed" all our tests. So, we shipped it :-D :-D :-D
I had never seen anyone actually "turn white" untill the day someone broke the code open and informed the CEO (it was also a small company) what we'd just shipped. You could almost see the blood drain out of his face like a thermometer that had just gotten thrown into a blizzard.
I guess it must be the part of me that is my evil twin that still remembers that so fondly...