Swarthmore invests in "private equity" -- non-traded companies -- and does very well. Total endowment is $1.9 billion with a one-year return of 17.8% and a ten-year return of 8.8%.
http://www.philly.com/philly/business/20150720_Richly_Endowed.html
http://www.philly.com/philly/business/20150720_Richly_Endowed.html