I wrote a paper with two different ideas for a coin with a stable price. By that I mean a price that does not change so abruptly as of now. None of those ideas involve a central authority, oracle or asset peg, they do not require fundamental changes on how block-chains work.
It's a short paper, 6 pages. Initially it was available only as pdf but security concerned users asked for jpegs too.
Note: We are mainly discussing the second approach here, which honestly I think is better. You can jump to section 5.
https://github.com/UmaPessoa69/coin-smooth-price
Note: I posted it some days ago on the economics section but it didn't get much attention and a user suggested bringing it here.