There are a lot of people using this, I am at http://jenius.me as well.
This was posted 3 days ago and rose to the top of hacker news when the original author released it, I don't understand why some other site is now getting credit for it or why a duplicate link is on the popular page of HN again...
Here's the link from 3 days ago, with over 170 upvotes: https://news.ycombinator.com/item?id=3468386