MegaHAL is a computer program written by Jason Hutchens that was entered in a contest on Artificial Intelligence.
From what I found with working with a copy I had on the computer, it's fairly stupid actually. Even so MegaHAL is still a good laugh.
What I got when I used MegaHAL to help me edit some of my screenplay
Some generally silly replies MegaHAL gave back in rensponse to questions about 'Tommorrow, When the War Began'