UPDATE: This is no longer free (as of Nov 1st, 2009)
Another one that was free in the Sony store for awhile and is now free for Kindle:
Mania
by Craig Larsen
http://www.amazon.com/Mania/dp/B002R...6903865&sr=1-1
$FREE
Product Description
A City Gripped By Fear. . .
Seattle newspaper photographer Nick Wilder has snapped his fair share of gruesome homicide scenes. But when a serial killer dubbed the Street Butcher takes his sick crimes to new depths of depravity, Nick finds the case suddenly getting to him in more ways than one. . .
A Killer Who Knows No End. . .
With each new murder Nick is shocked by what he won't soon forget. But the deeper he digs, the closer he gets to his own disturbing past--and the more he must risk to unmask an unpredictable, deranged psychopath. As the motives multiply and the suspects mount, the cold, stark Seattle winter is about to turn even chillier. . .
"Larsen taps into our deepest terrors. . . A fast and thrilling debut."--William Lashner, New York Times bestselling author of Blood and Bone
"Harrowing and twisted. . .a white-knuckle read!" --Gregg Olsen