At stack overflow, in our profile it tells you what percentile you fit into according to your reputation. Is there such a thing for hacker news? If you have the most karma, you're the top 0%, when you first register, you are in the top 100%, etc. This is something I want to build to learn ruby, but I want to know if it already exists first.
To the best of my knowledge, this does not exist. Ensure that you are at least familiar with <a href="http://news.ycombinator.com/leaders" rel="nofollow">http://news.ycombinator.com/leaders</a>, <a href="http://www.hnsearch.com/api" rel="nofollow">http://www.hnsearch.com/api</a>, <a href="http://jacquesmattheij.com/The+Unofficial+HN+FAQ#api" rel="nofollow">http://jacquesmattheij.com/The+Unofficial+HN+FAQ#api</a> and the rest of that document, be ready to be asked to stop, and enjoy!<p>(This doesn't look like a trivial application of any of the APIs above, by the way.)