The Prophet by Kahlil Gibran
Nearly everyone I know has read The Prophet, first published in 1923, at one time or another. Every time a person reads this book it speaks to you anew based on the place you are in your life at that moment.
It stands along side the Bible as one of the best selling books of all times. The Prophet is composed of 26 “sermons” given by a wise man. The wise man is about to return to his homeland after several years in exile when the people ask him to share his wisdom on the big questions of life, love, family, work and death.
This is a good book to open to a random page when you need support and insight.