usenet is a service offered by many isps...your mail client connects to a nntp server, and there are chat forums which are more or less topical, ie comp.lang.java is a forum on java programming. But people can also post binaries on to usenet, and so it is sometimes used for file swapping. I've been simply astounded at the sizes of some of the things I've seen posted in the movie forums, in what was originally intended as a text message board. Try alt.binaries.sounds.mp3.2000s sometime.