I had to look up this article by the late Sasha Chislenko for a paper I was reviewing today, and I am delighted that it is still available at its original URL, though Chislenko himself died in 2000. I've bookmarked the page on systems dating back to 1997 but I don't think I've ever done so on this site, so here it is, still open to the world. Chislenko was writing in public way before it was fashionable and, I think, probably before the first blogs - this is still and, sadly, will always be a work in progress.

This particular page was one of a handful of articles that deeply influenced my early research and set me on a course I'm still pursuing to this day. Back in 1997, as I started my PhD, I had conceived of and started to build a web-based tagging and bookmark sharing system to gather learner-generated recommendations of resources and people so that the crowd could teach itself. It seemed like a common sense idea but I was not aware of anything else like it (this was long before del.icio.us and Slashdot was just a babe in arms), so I was looking for related work and then I found this. It depressed me a little that my idea was not quite as novel as I had hoped, but this article knocked me for six then and it continues to impress me now. It's still great reading, though many of the suggestions and hopes/fears expressed in it are so commonplace that we seldom give them a second thought any more.

This, along with a special issue of ACM Communications released the same year, was my first introduction to collaborative filtering, the technology that would soon sit behind Amazon and, later, everything from Google Search to Netflix and eBay. It gave a name to what I was doing and to the system I was building, which was consequently christened 'CoFIND'  (Collaborative Filter in N-Dimensions). 

Chislenko was a visionary who foresaw many of the developments over the past couple of decades and, as importantly, understood many of their potential consequences.  More of his work is available at http://www.lucifer.com/~sasha/articles/ - just a small sample of his astonishing range, most of it incomplete notes and random ideas, but packed with inspiration and surprisingly accurate prediction. He died far too young.