The 1998 PC horror title Sanitarium is now only just $3.99 on GOG.com.
The point and click horror title has a little in common with recent horror title Amnesia. Both protagonist must figure out who they are, while escaping a world of madness. The game is thirteen years old, so no worries about running it. Sanitarium was also well received by critics in its prime, so expect a scary good time albeit a little dated.