I have on the order of 200 entries on my friends list. I've never met the vast majority of these, nor am I likely to. A large chunk of them aren't actually meetable, because they aren't actually people at all.
Long before I started reading Livejournal I was reading a variety of newsfeeds via Radio Userland. This tool allowed me to collect news from a variety of different sources into one place where I could read them at my leisure. It meant I no longer had to go searching across a multiplicity of different sites to see if any of them had posted anything new and saved me a vast amount of time.
I tried a variety of different newsreaders after that, ranging from Amphetadesk to Feedreader, always looking for one that would simply display my multiple feeds in a vaguely useful way. I already had a way of keeping track of whay my friends were up to - my livejournal friends list - what I wanted was something similar for reading news with. The most important thing about this program was that it had to be somehow accessible from wherever I was - otherwise I wouldn't be able to check news from both home and work without somehow synchronising where I was up to, something that would be tricky at best.
Someone in the LJ development team obviously felt the same need, because from out of nowhere came the Livejournal syndication system. Suddenly any syndicated feed could be viewed within Livejournal and added transparently to your friends list. Which was nice.
Less nice was the fact that these new 'friends' were interleaved chaotically with my actual friends. And there were far more entries from the newsfeeds than there were from real people - after all, the BBC alone would frequently have 20-30 stories on their feed. Add Slashdot, The Guardian, The Register, New Scientist and a host of other small sites (Neil Gaiman's journal, Warren Ellis' Blog, Greg Costikyan's journal) and suddenly it was very easy to miss the posts by people I cared about.
Fortunately there was a simple solution - friends groups. By creating a friends group called News and adding all of the newsfeeds to it, I could simply go to
http://www.livejournal.com/users/andrewducker/friends/news to see all of my daily news in one place.
Once the syndication system got going, feeds for pretty much everything sprung up. When the site itself didn't provide a feed (less and less common as time went on), people set up screen-scraping programs to extract the text from the site into a separately hosted feed. Some of these included comics, which I filtered into their own friends group -
http://www.livejournal.com/users/andrewducker/friends/comics/ - removing the last daily trawl I'd been making.
What brought this to mind was being removed from the friends list of
adders, who was cutting out all the people he didn't know in person. He said, however, he'd added me to his aggregator. Which left me wondering - why take me off of one aggregator (which is part of what LJ does, after all) just to add me to another?