Most surprising voice I've heard is definately
Hangtime. After reading his posts here, I expected a hard, slow southern drawl. But as Swager said, Hangtime has a very friendly, mild-mannered voice with nary a trace of southern accent. I initially had a hard time believing it was Hang.
Most interesting voices: Have got to be my Polish Squaddies,
Bikekilla and
Asmodan. Hearing those two yell in Polish while we're in the middle of a dogfight is something else!
Oh, and Cobra: That's Hedly!