Richard Feynman tried them out several times and had really interesting experiences. See <a href="https:&#x2F;&#x2F;www.dmt-nexus.me&#x2F;forum&#x2F;default.aspx?g=posts&amp;t=51786" rel="nofollow">https:&#x2F;&#x2F;www.dmt-nexus.me&#x2F;forum&#x2F;default.aspx?g=posts&amp;t=51786</a> for his description.