Trilobyte Games says The 7th Guest is now available in the Mac App Store. It sells for US$9.99 and requires Mac OS X 10.6 or higher.
Here’s how the game is described: “In the world of The 7th Guest, you are an active and mysterious entity known only as ‘Ego.’The house of The 7th Guest is filled with 19 devilishly clever puzzles that will test your wits and scare you out of them as well. To complete the game you must solve every puzzle in the house. Only then will the secrets of the madman Henry Stauf be revealed to you.”