Since

Since is chrome extension that highlights new post on hacker news' front page since your last visit. Why? Because hacker news doesnt sort new posts on the front page by time posted and it is easy to miss them

How to Install - 

1. Download zip file from here and extract it to a folder
2. Type chrome://extensions in your chrome browser's url
3. On the top right corner click on "Developer mode"
4. Then click on "Load unpacked" and click on the extracted folder and click open
5. Your extension should be now loaded and work when you visit hacker news