[ctkrohn]

Believe it or not, there's a novel that combines pretty much all these things: Charles Stross's "The Atrocity Archives." If you're into sci-fi, you need to check this out. It's a bizarre but hilarious mashup of James Bond, Slashdot, Office Space, and H. P. Lovecraft.

[pavel_lishin]

I would actually recommend A Colder War, which actually mentions a subterranean lake, and is also available to read online for free: http://www.infinityplus.co.uk/stories/colderwar.htm