K5 as it was usually shortened to, had a few very interesting people on it back in its heyday such as Micheal Crawford who wrote about Living with Schizoaffective Disorder and localroger who wrote The Metamorphosis of Prime Intellect. It was reddit with all the weird kids.
Michael Crawford is here on HN, in case you were wondering. When I first saw his name, I definitely did a double-take and had flashbacks to his OggFrog posts. https://news.ycombinator.com/user?id=MichaelCrawford
I nearly forgot to mention mindpixel AKA Chris McKinstry, I remember his suicide was a such shock. I can't think of anyone else who could write about mind and thought, and hypersurfaces and Hopf maps in a suicide note.
