Over the last couple of days I've told several people about Dallas Willard, and encouraged them to dig into his writings. Something I've told them I have not mentioned here before. The two books by him that I know best are Hearing God: Developing a Conversational Relationship with God and The Spirit of the Disciplines: Understanding How God Changes Lives. Bearing in mind that Willard was a Husserlian phenomenologist, I think Hearing God is essentially a phenomenology of religious experience, and The Spirit of the Disciplines is a theological phenomenology of the body, how the body influences the spiritual life.
The spiritual books of his that I haven't read yet are The Great Omission: Rediscovering Jesus' Essential Teachings on Discipleship. However, I have read several of the chapters, as they were published as articles prior to the book: I provided some of the links to these chapters here. The other book is Knowing Christ Today: Why We Can Trust Spiritual Knowledge, which I mentioned here. I started it yesterday.