For me, it's not really a matter of taking the summer off. Since I am an adjunct, I am last in line when it comes to summer classes. As often as not there is nothing left over. So I look for work (unsuccessfully this summer, thanks to the depression), and if I can't find it I try to budget creatively enough not to end up on the street before the middle of August.
The up side to all this is that I usually have time to do a great deal of writing and reading during the summer. Perhaps 90% of my writing is done during the summer, and often I can work my way through most of my stack of books-to-be-read that accumulates during the semester. Long stretches of uninterrupted time abound. Sweet!