I am very grateful to the ministry of John Piper. He has been influential in the lives of many of the preachers that I listen to and I read a great deal of his sermons as I prepare for mine.
One of the great things about John Piper is his generosity. This is shown through the vast amounts of material that he gives away at his website, DesiringGod.org. At this site, you are able to get audio sermons, sermon transcripts, and PDFs of books that he has written.
Today, in honor of Martin Luther King, Jr. Day, John Piper is giving away copies of his newest book, Bloodlines. It is available in a PDF format by visiting the link below. I don't know how long it will be available, so it is best to hurry.
Bloodlines: Race, Cross, and the Christian by John Piper.