Penn Jillette is an eloquent spokesman for libertarianism (people should be free to do whatever they wish with their person or property, as long as they do not infringe on the same liberty of others).
By eloquent, I should caution, I mean clear and emphatic. Penn is very profane, as well. If you don’t believe that “profanity is part of a good vocabulary”, you may be offended by the Penn and Teller Bullsh*t video series.
To see a sample — making the argument that the war on drugs is bullsh*t — click PLAY, or watch the 30min video on Google Video.
Rick McCharles 
Many thanks for the link to this excellent video.