The Ninth Circle has been tempting me for a while now, and it's just clamoured itself to the top of the pile (that I was restacking anyway).
From the Blurb:
A man comes round on the floor of a shabby flat in the middle of Budapest. His head is glued to the floorboards with his own blood. There's a fortune in cash on the kitchen table. And he has no idea where, or who, he is.