> Did you know that if you take the letters HAL and advance them each one letter, you get IBM? Is that serendipity or subliminal messaging?

It's serendipity, according to Arthur C. Clarke, who ought to know. I read an interview in the newspaper less than a month ago in which he was moaning about how everybody assumes he named HAL for secret conspiracy in-joke subliminal reasons. He says he didn't even notice the IBM thing until six thousand gibbering fans started mentioning it to him at every opportunity.