Rose and I used to be close to a writing group that got together to publish their own shared-world stories. It was a lot of fun, sort of a mini-fandom. Plus, we both liked their writing, so it wasn't just that we knew two of the four guys involved and were friendly with them. Anyway, I found their efforts inspiring at the time... sort of, "if this guy I know can write such good stuff, why shouldn't I try it?" Of course, each of them was a much better writer than I...
By the way, each year they participated in the 3-day Novel Contest. They web-published their stories as they were written, with commentary posted on their own message board. It was quite a lot of fun, waiting for parts to be posted and discussing the stories with other fans in more-or-less real time!
Three-day novels? Ouch. Hurts to even think about.
But that's really cool! I'd love to have writing pals in RL but no. Just online. Oh well.