node update, 6/03: Mysteriously, the previous writeups in this node have disappeared. Although it has been established that the phrase is used in the Sam and Max comics, a query as to the origin of this invitational phrase was explored. Below is my take on it.
The pseudo AI/conversation program might be a sort of Markov Chainer. Several MOOs have used the idea of Markov chaining to play with conversations made, allowing an object to comment back with 'cut-up' mishmashes of previous dialogs.
For example, Two people might have been wandering the rooms of a MOO, and one of them asked the other to follow them. At the same time, another persom might have been impersonating the Skipper on Gilligan's Island. Another person might have mentioned how they smelled flowers while nude, and another person in the room might have attained Message 3883 on a Maillist. The Chainer, MegaHAL, listening to these various conversations, when prompted, spewed the line above.
for a sample of Markov chaining in Alice in Wonderland with The Bible, see http://www.eblong.com/zarf/markov/revelation_of_alice.txt .
Go up a level for another explanation of Markov.
One MOO, DownMOO, uses a markov chainer in a chatbox setting, listening in to the entire babble, and any player may then ' markov' a sum-up of what has been said. The results are often amusing.