After making Hacker News Inline Reply I wanted to make a more complicated Chrome Extension. I have always liked the Reddit Toolbar, so I decided to replicate the experience for Hacker News.
Clicking the link above will get you the Chrome Extension for the HN Toolbar! The HN Toolbar is a combination of a Chrome Extension and a Sinatra app running on Heroku. The Chrome Extension redirects external links on the HN home page to the HN Toolbar website. The website then loads and styles the comments alongside an iframe of the content page. To get around iframing restrictions, the Sinatra app actually proxies all linked content on the framed page, which was most of the challenge in building this.
You can see all of the code for the toolbar and the extension on my Github under the hntoolbar repo.