Thought this was a worthy read considering how many internships I've seen that are unpaid. Apparently its illegal to make an intern work for free without teaching them something. Not that it would necessarily be a bright idea to bring this up with the boss
http://www.nytimes.com/2010/04/03/business/03intern.html?src=me&ref=general
http://www.nytimes.com/2010/04/03/business/03intern.html?src=me&ref=general