is a unique "interactive novel" that tells one of the best sci-fi stories ever.Returning from a failed 100-year voyage to earth, you find that that everyone has mysteriously disappered. Then you discover HOMER, a biological computer that alone holds the link to the past and conduit to the future. Together, you and HOMER must discover the doorway to humanity before you're stranded forever. "Puzzles" (in the loosest sense) involve accessing various databases to uncover more information. Highly recommended, especially to sci-fi fans.
Update: The entire text of the game (and the novel that succeeded it) is now available on-line, thanks to Salim Fadhley and Rob Swigart himself who granted permission to distribute his great novel under the GPL license. You can read the book here or follow a related link below :)