Here is a collection of extensions/scripts I have written for Google Chrome and Firefox's Greasemonkey plugin.
Hacker News OnePage
Hacker News OnePage is an extension for news.ycombinator.com. Hacker News is an excellent community sharing articles and thoughts around programming and startups.
Hacker News OnePage allows you to view the list of news articles in a left column, while viewing the article or comments on the right. You never have to leave Hacker News to view any of the comments or articles. OnePage also highlights the articles and comments that you click on, allowing you to easily see what you have read.
I use this everyday and pretty much can't live without it!
The main objective of this extension is to remove the annoying flash banner ads on digg.com.