There are plenty of such stories on various interactive sites here and there, but it could take a little digging.
From The Overflowing Bra:
Happenings (you may need to page down to see it in the author list). First, everyone but teenagers disappears from the world, then there's BE and increased arousal, and it continues with more and weirder changes.
You have to pay for it, but there's a good world-changing story on the BE Story Club called "Big New World" -- might be worth signing up for (at least) a month.