I can't believe the stuff you can download for free. One of my favorite sites is Librivox where you can download audio for public domain books being read by people who have simply volunteered their time. The quality is surprisingly good, too. Along the religious lines, you can download some great classes at Biblical Training where Bill Mounce (who wrote my favorite beginning Greek text) got together a bunch of his friends (some no-names like Craig Blomberg, John Piper, Ronald Nash, Gerald Bray and Frank Thielman) and posted entire classes for free download. And on iTunes Elena recently directed me toward iTunes U where you can download whole classes for free from tiny unaccredited colleges like Stanford and MIT. Back on the religious side I've also downloaded some outstanding things from Sermonaudio.com. I thoroughly enjoyed listening to A.W. Tozer preach, for example. I guess you probably have to be a big nerd to enjoy this stuff but this world sure is getting a lot more enjoyable for nerds like me.