“More than 2.3 million people were locked up in federal, state or local systems at midyear 2007, according to the U.S. Dept. of Justice, and they want their Michael Jackson and Pink Floyd just like everyone else. Enter North Hollywood-based Pack Central, which runs a mail-order operation for about 50,000 prisoners. It stocks about 10,000 CDs and 5,000 cassette titles.”