Coherent (a unix-like OS for ``IBM compats'') used a version of the Enigma
rotor machine. Although allegedly broken in WWII by several allied
countries operating autonomously, it is significantly more difficult to
break than XOR by a small key.
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VaX#n8 (vak-sa-nate) - n, CS senior++ and Unix junkie - vax@ccwf.cc.utexas.edu
Information Freedom Fighter                           - PGP key on request