Not sure if it's already been mentioned, and want to go over the whole thread slowly so I can check up on the recommendations, but I just finished reading The Variant Effect:
http://www.goodreads.com/book/show/8...variant-effect
Very good and different take on zombies, it's more 28 Days Later zombies than Romero's shuffling horrors, so expect lots of action and bodily fluids spraying.
Book 1 is free, the second is less than a Starbucks, and there's a free short story at the end, they aren't terribly long which is a bit annoying as I want to see more of this world, but I recommend them whole heartedly.
It wins my award for "most cringe worthy sex scene ever" as well.