Pyst
From MYSTlore
Pyst was a parody of Myst, made by Parroty Interactive (Wikipedia). It came after the overwhelming success of Myst, which at the time had sold over four million copies. Released in 1996, three years after Myst had been, the premise of Pyst was that the many players of Myst had overrun and cluttered Myst Island, turning it into an awful-looking tourist resort. Pyst featured a number of slides (all based on nodes originally from Myst itself, but heavily modified), but little to no gameplay or storyline.
Myst and Riven Illustrated has all slides of Pyst on its humor page. "A for Adventure" has a review, and GameWinners.com found an easter egg.
[edit] Driven
Parroty Interactive later started working on a sequel, Driven, which was supposed to be a parody of Riven. It was, however, never released.

