Can you recommend similar games? (Aside from Penumbra)

[darkpast]

Call of Cthulhu: Dark Corners of the Earth. There's weapons, but large parts of the game (like the first 1/3) you can't get any. Plenty of stealth. Some puzzles, but most aren't difficult. Great atmosphere. It has plenty of bugs, though.

Darkness Within maybe. It's a straight-up adventure game though. I thought it had a good story and atmosphere (very Lovecraftian), but the critics tore it apart when it was released. Probably because of the slow pacing and antiquated graphics.