[Kristine1975]

>but money is not the only thing of value an internship can (or should) provide.

Of course not. But unpaid internship is always exploitation.

[aries1980]

…and illegal in many countries, including the US unless “the employer that provides the training derives no immediate advantage from the activities of the intern” what I can hardly imagine it can realistically happen. http://www.dol.gov/whd/regs/compliance/whdfs71.pdf