This seems a solved problem: Make an Ask HN asking if anyone here can give the link to the story you vaguely remember. I've seen it work several times, usually

This seems a solved problem: Make an Ask HN asking if anyone here can give the link to the story you vaguely remember. I've seen it work several times, usually very quickly. Side-benefit: You might find related stories, or help other people discover the story for the first time.