Usenet

In the many years I've been using computers, with much more intensity than ability, I've never really had too much to do with Usenet.
But it's interesting that the Usenet system actually predates the World Wide Web by more than 10 years. Here's a useful video that explains in a non-technical manner what Usenet is. Probably the best recent guide to getting set up to use Usenet is from Lifehacker.
Anyway, first you need a Usenet service provider and it seems you have to pay for them all. I chose Giganews just because there's a 6 day free trial period.
Actually, Giganews have some great videos (note that there are 9 videos in this series) to run you through the various stages to get the most out of Usenet.
Once you have your service provider you then need, but only if you want to read, or post to, the newsgroups, a NewsReader.
Although I'm not a Windows user, I actually used Outlook Express for this (and as this isn't available in Windows 7, I used Windows XP) mainly because the free Reader I installed for my Mac (OSXnews) was crap.
Now I have to say that the so-called newsgroups really did not excite me. They're very similar to Google Groups and I didn't see anything that I couldn't get from the plethora of forums on the topics I'm interested in (Linux, OS X and Haiku).
So, I really don't see myself going back very frequently to Usenet for this purpose.
However, what I did find potentially very useful was the .nzb file concept. Essentially, this is where you can download substantial stuff like movies and music.
It's similar to bittorrent but there's one big difference. The download speed is immense. Ingeneral, for me, I downloaded stuff from .nzb files at my maximum ISP download rate.
To use .nzb files, you first need an index of available stuff. I've only used nzbindex.nl which is free.
Type what you want in the Search box (Advanced searches also available where you can, for example, specify a minimum files size) and click Search.
Then you pick the one you want and click download to download a small .nzb file to your computer.
Now, you need something to download the actual file you want (remember the .nzb is almost like a torrent). On my MacBook, I used Unison for which again there's a six-day free trial.
Works great and you can very quickly get a lot of stuff for free as the download rate is phenomenal.
Note, however, that a lot of the files that show up in an .nzb search don't refer to exiting files (or articles as they're called). This seems, from my very brief experience, to be particularly the case for older items.