I like books that help me co-operate with God's power that is working to transform me on the inside. There are a few current publications but most of the really good ones were written some time ago.
I like books by authors such as; T. Austin Sparks, A.W. Tozer, Spugeon, Finney, Luther, Joseph Parker, Charles Elliot Newbold Jr. and Manfred Haller to name a few.