Usenet was the first time I interacted with the internet as it was the only thing accessible from the Unix lab we had access to (email was available but we didn't use it). This was 1994. I was on alt.music.pink-floyd during the height of the PUBLIUS ENIGMA puzzle.
I kept using it up into the early 2000s. I'd jump on in the morning before going to work, and that's how I found out about 9/11 (it was 12:46am NZ time when the first tower was hit). I had gone to our local newsgroup for our city and there were messages in all caps "TOWER COLLAPSED" and then "BOTH TOWERS DOWN". I wondered what was going on, then turned on the TV where our main channel was feeding in the live news (I think it was CNN). We just sat there horrified, watching before we eventually went off to work.
I eventually stopped using it when web forums and other sites took over for me (fark, slashdot, metafilter) and then my ISP dropped support for it. Google Groups didn't mesh with me and I never went back.
When I first jumped on here and got my head around federation, it took me back to those Usenet days because in a sense this is almost the same. I've seen lots of people say "federation is like email", but to me it's like Usenet.
There's a gif of random coloured splats covering it over. When it first went up it had a snoo with SPEZ written in white on a red background for its eyes. It was heavily brigaded. If you click on any random spot it's most likely a brand new bot account, or a bot account from last year.