Grimrock

Ambient drone music goes really will with Grimrock, you can even play both and it will mix up and make an awesome atmosphere

I guess that I am stuck in my ways and feel you can't get a better atmosphere than what the old Dungeon Master had.
Funny really, they must have been very restricted to what they could add to DM, due to memory and hardware. Yet by adding less they created more.

UPDATE: I am now past the dreaded level 3. I gave those spiders what-for this time, there not so tough when you are holding a can of Zapp.