I have indeed. Ebon Initiate/Crusader/Ashen Knight.

With this PrC, Ashen Knight, and Krimm's Occult Adversary, I can do something I haven't done since Tome of Magic originally came out. I can make a triple focus character. (That one was arcane/divine/binding, this would be binding/maneuver/ebon initiate.)

And I would totally love to see a Ebon Initiate/Necrocarnum PrC!