> It was that a comment on a message board would lead to following them on LiveJournal...

I remember "back in the days"™ many forum software allowed a feature called "signature", it allows you to attach custom pictures and links after each and every post you posted. Many people use this feature to advertise their sites/blogs for others to visit.

Then the feature got weakened by both the social media platforms and forum software, to the point that it's gone and forgotten.

But based on my experience, it was the best place in the old time to do advertisement and SEO. I learned and bookmarked many interesting blogs from those signatures.

Now days, I'll just google it if I need anything, and never look back after I'm done. That's one reason today's Internet is dead to me.