GameSpy's PlanetFargo column this week is a very funny plan for setting up a bot to play your online role-playing games for you, including a scenario showing just how well this could work.
1. If someone says something ending in a question mark, respond by saying "Dude?"
2. If someone says something ending in an exclamation point, respond by saying "Dude!"
3. If someone says something ending with a period, respond by randomly saying one of three things: "Okie," "Sure," or "Right on."
4. EXCEPTION: If someone says something directly to you by mentioning your name, respond by saying "Lag."
5. (And remember to accept all trade requests from other players by giving them a melon.)
