Word of mouth. In the halcyon days of the late 90s, the social aspects of the internet were a lot more deliberate. You'd belong to online communities or established social groups, and people would actively tell other people they knew online about things they'd found in the weirder corners of the internet. You couldn't just blast out a context-free link to everyone you knew and have the platform take care of assembling a preview. It had to be worth your time to share, and people would complain if you spammed them with junk.
"Worth your time" is a pretty relative notion, though. It's worth mentioning that the web of 15-20 years ago was of very little "value" compared to what we have today. Some links I remember sharing on a mailing list circa 2000 include the Poorly Drawn Lamp Page [1] and the William Shatner Acting Simulator [2] (warning: the depiction of Sulu has not aged well).
"Worth your time" is a pretty relative notion, though. It's worth mentioning that the web of 15-20 years ago was of very little "value" compared to what we have today. Some links I remember sharing on a mailing list circa 2000 include the Poorly Drawn Lamp Page [1] and the William Shatner Acting Simulator [2] (warning: the depiction of Sulu has not aged well).
[1] - http://www.flamingmayo.com/poorlydrawnlamps/
[2] - http://simshatner.fanspace.com/