In 2000s there used to be external wikis for ops done in a local BBS in my country, and those used to summarize timelines and key informations that led to development. They were probably doing for their own fun but were also useful for defending side.
There has been a long slew of young girls (and some boys) who have been tricked into sending explicit photos and have had their lives ruined over it in connection with 4chan and sites like it.
Like “04/01 15:00 target posts a picture[link, deleted] location[link] verified from vegetation, angle of sun and buildings in background. 19:34 A member discovers that face in reflection matches photo[link] taken by target’s acquaintance A”.
From logs like that, defensive sides can learn that you shouldn’t upload a picture with features that can be correlated from satellite imagery, that you generally should not upload your friend’s face, that you should also check reflections before uploading, that it’ll take few hours to analyze a photo, etc. (btw these are why I don’t do Fb/Ig or TikTok — it goes against every fucking best practices I had accumulated)
Or maybe this could be a new business idea…
They thankfully didn't find me in real life, but I pulled down all social media to avoid them.
Edit: I want to say one more thing. Sometimes people defend 4chan and say stuff like "that's just how they are", "they don't really mean it", or "you have to understand their community". But places like 4chan do real, measurable harm to people.
Just recently, Near/Byuu (SNES emulation) took their life after relentless doxxing and harassment. It wasn't 4chan, but these communities all harbor the same type of anonymity-enabled "for the lulz" harassment that brings out the worst in people.