The devil is in the details... I'm not sure that's possible! :-) Yes, yes, I know, the architecture is deader than a doornail for serious use, but I liken it to sailing vessels: nobody uses them for serious cargo haul any more, but they are still much beloved (and for good reasons, IMO). The PDP-11 is an incredibly elegant architecture, perhaps the best ever (IMO), which remains one of the very best examples ever of how to get 30 pounds into the proverbial ten-pount sack - like early UNIX (more below). Nah, it's just a clever hack (small-scale). What is really, almost un-approachably, brilliant about early UNIX is the amount of functionality they got into such a small machine. It's hard to really appreciate, now, the impact UNIX had when it first appeared on the scene: just as it's impossible for people who didn't themselves actually experience the pre-Internet world to _really_ appreciate what it was like (even turning off all one's computers for a day only approximates it). I think only people who lived with prior 'small computer OS's' could really grasp what a giant leap it was, compared to what came before. I remember first being shown it in circa 1975 or so, and just being utterly blown away: the ability to trivially add arbitrary commands, I/O redirection, invisibly mountable sections of the directory tree - the list just goes on and on. Heck, it was better than all but a few 'big machine' OS's! Eh, de nada. Noel