Every once in a while one hears about crazy kids eating the seeds of Jamestown weed or Jimson weed to get high. The high that is experienced is similiar to the high from oooh I dunno, eating rat poison. All of the hallucinogenic effects are actually just the body responding to the deadly poison that is Jamestown weed.
To review: If anyone offers you Jamestown weed just say no, that shit is poison which is a variation on the more misguided just say no. Be prepared to call poison control if you do see anyone taking it. No one really wants to be in a coma on the verge of death, do they?