GOOGLE -- If you're investigating instances of prior art, one place to start your trawl of the readings would be in Google Groups. Google has fully integrated the past 20 years of Usenet archives into Google Groups, which now offers access to more than 800 million messages dating back to 1981. This is by far the most complete collection of Usenet articles ever assembled and a fascinating first-hand historical account.
Google Groups compiles some especially memorable articles and threads in its USENET timeline. For example, read Tim Berners-Lee's announcement of what became the World Wide Web or Linus Torvalds' post about his "pet project".
Google Groups -- "20 year Usenet Timeline" and more about USENET Timeline.