I think the Benghazi attacks happened live on the forums. One of the people killed at the embassy was a gamer and posted often because he had a space guild or something.
Notch released beta versions of Minecraft there for people to "check out what I'm working on"
A LOT of stuff happened on the forums. It was nuts.
The Franz Ferdinand meme everyone is going off of (which makes a TON of sense if you witnessed it and even briefly think about it) is that we would have avoided Donald Trump if lowtax had not banned hentai on the forums.