Just like the Internet... :-) Sorry, are you referring to his work on computers, or his work in code-breaking too? If this latter, I would have to disagree. Respected military historians have suggested (of course, such alternative history is always speculative, one can't prove it) that the code-breaking work of the Allies shortened WWII by up to two years. I doubt mechanical fire-control computers (which is the primary military use of ball-and-disc integrators, as I understand it) had that significant an effect. Well, two things. (And don't get me wrong, I admire Zuse and his work.) First, Zuse's work didn't really have much impact. You may disagree, but my sense is that if that bomb that destroyed the Z1 had gotten him too, the post-WWII world would still look pretty much like the real one. Second, his early machines (Z1-Z3) weren't stored-program (in the sense of 'one memory holds both instructions and data'). Yes, yes, I know the Z3 can (with a monstrous kludge) be Turing-complete, but it still wasn't stored-program - which to my mind, is _the_ key aspect of a real 'computer'. Interestingly enough, Babbage's machines weren't stored-program either; they had separate instruction and data tapes, like Zuse's (although they had conditional branching, which the Z1-Z3 didn't). Turing's invention of thex stored-program in 'On Computable Numbers' was really a fundamental leap. Noel