The Department of Ed has released its <a href="http://collegecost.ed.gov/catc/#">annual lists of the colleges with the highest/lowest tuition and net prices</a>, and a good summary is available <a href="http://www.insidehighered.com/news/2013/06/28/education-department-releases-annual-tuition-pricing-lists">here</a>.
One nice thing about this list, as opposed to how "most expensive" data has been shown other places, is that in addition to listing the highest tuition as per the college catalog, it also lists net price, which takes into account financial aid. So, yes, Columbia University has the country's highest tuition, but it doesn't appear on the highest net price list.
But I noticed one particular finding: Among private, not-for-profit colleges, the music and art schools are way expensive. The top five for net price (and seven of the top ten) are art or music. Arts instruction is expensive because there is so much one-on-one teaching. Yet - what kind of earning potential do their graduates have? In current discussions of the cost of college, the job market, and both institutional and individual accountability, this is one sector that hasn't received much criticism. If we're going to discuss whether it's smart to get a philosophy B.A., we should also discuss whether a B.F.A is a smart move.