Cyan Worlds recently released a free version of Myst that will allow you to relive some of the 1993 classic adventure game. While technologically rather simple from today's standpoint (mostly static images), the game's graphics and soundtrack were remarkably immersive. The game starts you on a strange island where you must explore your surroundings, solve puzzles and figure out the backstory.
The free version of Myst allows you to explore Myst island while the full has 5 additional ages to explore. Removing that additional content shrinks it down to 124MB, so still a sizable download. Meanwhile, the full version has dropped $1 to $4.99.
If you've never experienced Myst, here's your chance.