"Judas and the Gospel of Jesus" (N. T. Wright). This book is an excellent analysis of some of the claims made relative to the discovery of the "Gospel (sic) of Judas". He presents, point by point, excellent evidence that this 'Gospel' is the exact opposite of the canonical Gospels on every important point.
The Judas book is representative of what is called "Gnosticism". There were many people and subdivisions within the gnostic movement, but a characterizing belief was "gnosis" or "secret knowledge". This idea is a popular one, which can reappear any time.
Wright makes a small attack against dispensationalism at the end of the book. And I am convicted by it. He claims that dispensationalists are not unlike gnostics in their desire to escape the "evil" world. I think this is a real danger. We must remember the call to be salt and light, and not to give up on the earth. As caretakers of the earth, we should conserve, for God "shouldest destroy them which destroy the earth" (Revelation 11:18)