I am reading a brand new book right now by my good friend- Tullian Tchividjian- titled Unfashionable: Making a Difference in the World by Being Different.
Tullian has a unique perspective on the Church, Christianity, and living within and outside the "Christian bubble." As the grandson of Billy Graham, he's had life experiences that give him incredible insight into the always pressing question of how do we as followers of Christ live in the world but not of the world.
He recently was hired to lead Coral Ridge Ministries, and is merging the ministry of Coral Ridge and New City Church, the church Tullian founded in 2003.
Tullian wrote this most recent book to make the case that Christians make a difference in this world by being different from the world- challenging Christians to be courageous enough to be different.
Check it out, and pick it up.