On: How to look for Hacker news old post?

[riffraff]

if you upvoted the link, it's under http://news.ycombinator.com/saved?id=your_id

if you posted a comment you can find under http://news.ycombinator.com/threads?id=your_id

Otherwise you have to try using the search box which is at the end of every page (which uses http://www.hnsearch.com/)