Shaped like clovers, festooned with Playboy bunnies and popular cars, the colorful little Ecstasy pills that landed the owners of two popular downtown clubs in jail last week started their march to Houston in clandestine, rural laboratories in the Netherlands. Chemists, sometimes working out of large, sophisticated buildings, sometimes mobile laboratories, have churned out as many as 500,000 Ecstasy pills an hour for a mere 20 cents each, making the Netherlands, a country known for its liberal attitude toward the illegal pursuit of happiness, one of the major worldwide producers of Ecstasy. Last week's charges against 24 people in Houston...