"Walter Benjamin, in his prescient 1923 essay "One Way Street," said a book was an outdated means of communication between two boxes of index cards. One professor goes through books, looking for tasty bits he can copy onto index cards. Then he types his index cards up into a book, so other professors can go through it and copy tasty bits onto their own index cards. Benjamin's joke was: Why not just sell the index cards? I guess that's why we trade mix tapes. We music fans love our classic albums, our seamless masterpieces, our Blonde on Blondes and our Talking Books. But we love to pluck songs off those albums and mix them up with other songs, plunging them back into the rest of the manic slipstream of rock and roll. I'd rather hear the Beatles' "Getting Better" on a mix tape than on Sgt. Pepper any day. I'd rather hear a Frank Sinatra song between Run-DMC and Bananarama than between two other Frank Sinatra songs. When you stick a song on a tape, you set it free."