That overprint stroke method works for simple stuff. It gets tricky when you have single objects that both trap and butt, or trap to several different colors or trap on one side but not on the other. I wind up having to hand build the traps on lots of my stuff. I was using a free demo of this trapping software for a while http://www.esko.com/web/site.aspx?p=380, it was awesome. It cut complex illustrator trapping jobs down from 4 or 5 hours to 30 minutes. But it costs $3200
Brg!
Barricades of hamburgers divide the nation.
it's mostly nice that someone took the time to explain the concept of trapping and separations thoroughly. i may just be sending that link to all my clients from now on (i hate doing it, even though i can charge for it).