The first time I started trading was back in 2000 (a bumpy year unlike 1999). I found that my weakness as a trader was that I had no... um... well, lets say confidence and know what I mean. I could figure out trades on paper, I knew what I should do, but I carried too much fear and wished I could just program into the computer what I wanted to do and then close my eyes and run away. Okay, I'm exagerating, but the point is, that my weakness was what I think most great traders have in spades. So for me, the appeal of automatic trading is the removal of the live me messing up the trade. Fortunately, I also have more cash reserve now than I did in 2000, so I'm in a better position to handle the down time.
That said, it seems like quite a few people have working automation systems. Of course, I've never seen the machine doing it myself.
My goals right now are very humble compared to what some people are doing. I'd be happy with a yearly return of what Boris Stein is getting per month. (The again, I'm not doing futures for a very long time, just equities.)