Earlier today, my good buddy Dan alerted me to something called Salvia
While reading the information on that website several things occurred to me
1) It is completely legal
2) It is completely natural
3) It only lasts 15-20 minutes
That said, I don't think that I would ever have the courage to try any substance that could trigger schizophrenia and requires a sitter to keep you from hurting yourself.
But wow, I had no idea that such a substance existed!