You may recall recent comments by Attorney General Janet Reno where she notes that exportable encryption cannot be broken in reasonable time by modern supercomputers. With that as background, you may find the following paragraph interesting. It is from the Financial Times article on Colossus. http://jya.com/coloss.txt
[Tony] Sale describes [Colossus] as a large electronic valve programmable logic calculator. "No lay person would argue that it is not a computer," he says. Furthermore, because it wasted no time retrieving a stored program it was almost as fast as a high-speed modern computer whose nominal work-rate is 1,000 times quicker. A simulation of Colossus which Sale ran on a top-of-the-range Pentium PC took twice as long as the real thing.
Martin Minow minow@apple.com