I just finished the Chzo Mythos series of games. They're 4 independent point-and-click adventure games with a mystery/horror setting. The series was pretty cool, though the end posed more questions than it answered in my opinion. They each take about two hours to finish, but I recommend replaying the game with commentary on after you finish them. The commentary answers a lot of questions.

You can download them all for free at http://www.fullyramblomatic.com/games.htm

Titles in order are:

5 Days a Stranger
7 Days a Skeptic
Trilby's Notes
6 Days a Sacrifice

If you've ever been a /x/phile, I highly recommend the series.