This makes for an interesting read!
The highest ranking book that I have read was Mere Christianity at no. 3 by CS Lewis.
Of the 50 listed I have read:
49.Knowledge of the Holy
48.The Hiding Place
46.Out of the Saltshaker and into the World
42.The Purpose-Driven Life
38.The Gospel in a Pluralist Society
34.This Present Darkness
33.The Late Great Planet Earth (hehe!)
32.The Cross and the Switchblade
28.The Act of Marriage
26.Know Why You Believe
21.The Master Plan of Evangelism
19.The Cost of Discipleship
18.The Divine Conspiracy
17.What’s So Amazing About Grace?
13.Evidence That Demands a Verdict
11.Celebration of Discipline
9.Through Gates of Splendor
7.Rich Christians in an Age of Hunger
6.The Living Bible