Have you ever heard of WikiTalk? If you haven't, it is because it is a new social networking and an accumulation of interesting contents website. Something like stumble upon and digg and many like them. If you love stumble upon and digg, I believe you would like this. I say this because I checked out their website and I find it impressive.
When you go to the website, you would be able to see a collection of hot topics. These topics can be from blogs, from news websites, from youtube, product reviews, etc, that people submitted to Wikitalk. When you click on one of the topics you will see something like the picture below. I didn't install the plugin so I got the pop up on my screen. Click on the image and you should be able to see the picture larger view.

Below the site that you are visiting, there will be a frame where you can see the discussion going on, regarding the topic on that particular website.
By the way, the plugin can only be used with IE. I'm using firefox. So as you can see, I didn't even have to download the plugin, yet I still could browse the website. Though if you feel the need to join in the discussion, you need to register. The plugin is to enable you to start a discussion on any website that you are browsing, without having to go back to Wikitalk's page to submit it there.
I personally think it's like taking a discussion forum along with you while browsing! Since the site is something like digg, you would be able to find really interesting things to read.
The site has got my thumbs up. So don't miss to Check out the WikiTalk.com Public Launch!
A word of caution, you might get addicted to it.