Right now I'm re-reading "Farewell, My Lovely" by Raymond Chandler, mainly because I just finished the last book I lent out from the library and didn't find an appropriate replacement.

For anyone who goes for very well-written detective stories - this here's really a classic. It's the follow-up to "The Big Sleep", Chandler's very first novel, which was an instant success when it came out in 1939. Maybe "well-written" is even an understatement in this case. This is one of those rare books where there simply isn't any weak spot - it just goes bang-bang-bang.