A man pretending to be a woman.

Which was the success criteria, as well. The computer had to fool people as often as the man.

Alan Turing's test, the way he wrote it, is pretty hard. The variations are much easier. I had an entirely functional emulator named Katy.exe that was indistinguishable from a person suffering from catatonia. And I didn't even write it on purpose, I renamed another program that happened to work that way due to something stupid I did with a pointer.