#1 The Atrocity Archive by Charles Stross
Lovercraftian cold war spy thriller starring an unrepentant geek named Bob F.O. Howard. A re-read for me but this book and the universe it's set in is glorious - balancing existential dread with bureaucracy and making you think like the geek you are almost as much as Neal Stephenson does <3
¤2 Jennifer Morgue by Charles Stross
Sequel to the above, The Jennifer Morfgue has exotic locations, sexy foreign agents, and even a fluffy kitty. A great continuation of the saga of Bob, although I enjoyed the first one more.
#4 The Fuller Memorandum by Charles Stross
Third one in the series (#4 is out in July!) and the darkest one thus far. Starting with Bob darkly referencing horrible events, this is a book that deals with horrible human beings trying to do horrible things, sheds a lot of light on some of the characters and shows just how dark the world really is. My favorite in the series thus far.
All in all, the entire Laundry series wins a massive recommendation from me as a fan of urban fantasy, horror and spy novels.
#4 Skulduggery Pleasant: Death Bringer by Derek Landry
The 6th book in the Skulduggery Pleasant series, Death Bringer starts at a pretty dark place. The plot itself is simple - Necromancers have found their death bringer and it's end of the world as we know it - but this book is much more about the character development. it's full of snark and gore but mainly what makes it my thus far favorite in the series is Valkyrie's growing pains, her bond with Skulduggery and the awesomeness of the climatic fight that is full of character-y goodness. I highly recommend the Skulduggery Pleasant series to everyone. To me these books rate the same "for younger readers BUT..." as Harry Potter does.