I just finished (at 3am) the most releasable version of StackStalker, the new Chrome Extension that allows you to easily monitor any question you like, regardless of your membership status with StackOverflow!
I tried to make it simple, intuitive, and powerful, but mostly I wanted to create something that I would use. Hopefully it's useful for others out there too.
See the link for more details, and please give me some feedback, as this is my first Chrome Extension (and foray into the StackOverflow API)!
Thanks :)
UPDATE
Screenshot / Code Snippet

About
I always disliked having to sit there and refresh a question on any of the Stack Exchange sites waiting for something to update. I would rather ask a question, go do something else, and wait to be notified of an update. StackStalker is a Google Chrome extension created exactly for this purpose. It doesn't care who you are or what your personal stats are. You don't even have to have a Stack Exchange account to use it! Simply find a question you want to monitor the progress of, open the extension, click the "Add This Question" button, and go do something else! StackStalker will let you know when something is updated.
StackStalker is currently hooked up to all five participating Stack Exchange sites, but is constructed to very easily handle new ones. To monitor a question, you must be on that question's page to have the button appear. If you wish to stop monitoring any question (but want to keep it on your list), simply click the eye. To remove a question, click the red X.
Updates are defined by an update of score, answer count, accepted answer status, question comment count, and answer count. If any of these change, StalkStalker will let you know.
License
Free! Get it here
Download
Get it here from the Google Chrome Extension Gallery.
Platform
This extension is for Google Chrome only.
Contact
Created by me, Jason Edelman. If you want to contact me, my info is on the website listed in my profile, or you can just leave a comment here (I'll be monitoring this thread :)
Code
This was written entirely in HTML5, CSS3, and Javascript + jQuery. The code can be found by installing the app and locating it in your extensions folder.