First, take a look at “Wikihistory” by Desmond Warzel. It’s very short, and is presented as a log of a forum thread rather than a literal series of posts, but it captures the idea really well.
Then, browse the first few posts of one of the following blogs:
Welcome to Nightvale is a well-known fiction podcast/internet radio anthology series.
Consider how each form of each of these creates opportunities for and shapes contours of narrative: plot, character, audience interaction. In addition, try to make a mental account of all the production tools you would need to create something like each of these yourself.