Paul Tillich books beginning with Shaking of the Foundations through his Systematic Theology
Eric Fromm's Books beginning with Man Against Himself.
James Kugel: How to Read the Bible and others works.
Thomas Szasz: The Myth of Mental Illness; The Meaning of Mind: Language, Morality, and Neuroscience; many others.
The Bhagavad Gita by Eknath Easwaran
Aldous Huxley's Perennial Philosophy which introduces readers to many other wisdom writers.
The Dhammapada: various translations.
Nothing Special: Living Zen by Charlotte Joko Beck
Mindfulness in Plain English by Bhante Gunaratana
A Path with Heart by Jack Kornfield
Breath by Breath by Larry Rosenberg
How to Be Sick: A Buddhist-Inspired Guide for the Chronically Ill and Their Caregivers
How to Live Well with Chronic Pain and Illness: A Mindful Guide by Toni Bernhard
Everything Arises, Everything Falls Away by Ajahn Chah
Food for the Heart: The Collected Teachings of Ajahn Chah
Being Dharma: The Essence of the Buddha's Teachings by Ajahn Chah
The Self as Agent by John MacMurray
Reason and Emotions by John MacMurray
I watched The Unbearable Lightness of Being when I was 22 or 23 in the theatre after it came out; then again and again... Excellent film. I never read the book, which was unusual back then--I usually read the book and skipped the film.