A COPTIC GOSPEL OF JUDAS is evidently circulating on the antiquities market and Stephen C. Carlson of Hypotyposeis gives some information on it. (Scroll up for another posting on it as well as an additional mention of our own Jonathan Pennington.) There's also an entry on the Gospel of Judas in Peter Kirby's Early Christian Writings website.
The concept of a Gospel in which Judas is the (or a) hero is pretty interesting and reminds me of the Judas of the Last Temptation of Christ: perhaps yet another "Gnostic" theme in it. I wonder if Nikos Kazantzakis knew about the Irenaeus passage.