I recently stumbled upon Progress Quest, a freeware FAPBBMMORPG (Fully Automated Progress Bar Based Massively Multiplayer Online Role Playing Game) with a huge and robust single-player offline campaign.
Being a fully automated game, Progress Quest requires no player interaction, with the exception of character generation.
Once your character has been created, the game plays itself through a series of progress bars and lists, accepting absolutely no input from the player. It is surprisingly fun.
http://www.progressquest.com/