https://www.roleplayerguild.com/topics/191969-kingdom-of-threndel-beginning-of-the-end/ic#post-5504604
https://www.roleplayerguild.com/topics/185170-wh40k-lost-system/ooc#post-5238461
https://www.roleplayerguild.com/topics/182695-we-are-among-them/ooc
https://www.roleplayerguild.com/topics/182038-exodus-of-the-forgotten-realm/ooc

I can't find some of the others, but one was pretty much the last one but space, might have been from a different forum website. World building was always my kinda thing. Top one is the current one I am rping out and enjoying it a bit. 

The 40k one I turned into an only war game a few years ago, and rebooted that on roll twenty last year as well. Making it a 40k westmarch, works a lot better as a ttrpg than a forum one, but could still work as a forum rp.
TBF most of these I turned into ttrpgs, and they worked better, just haven't done the top one since not many people play earlier editions of dnd anymore, or pathfinder 1e.