A well chosen summer reading list can not only drive away boredom but it can help you prepare for the SAT. Learning vocabulary in context is the one of the best ways to increase your verbal score.
Slate has some interesting* recommendations from this 2010 article.
I'd suggest a mix of fiction and non-fiction to keep those brain cells working. Here are a few of my favorites:
Tattoos on the Heart by Gregory Boyle, S.J.
Under the Banner of Heaven by Jon Krakauer
East of Eden by John Steinbeck
Dubliners by James Joyce
and pretty much anything by Amy Tan, John Irving, Toni Morrison or Fyodor Dostoyevsky
*The Write College does not agree with brewing your own beer as a wholesome activity.