A new browser add-on by L.A.-based Border Stylo aims to bring the social web experience closer than ever before to the experience of sitting next to a friend and pointing to something on your screen. The Glass add-on (now in private beta for Firefox, coming soon to Google's Chrome browser) combines elements of social bookmarking, Facebook and the humble Post-It note.

Glass lets people talk about the Web with their friends in the bluntest way possible - by posting comments, photos or video in boxes on the page, directly over whatever headline, photo or element they want to highlight.

"Glass is a virtual canvas over the entire web where you can literally place notes on top of any website. Now, instead of sending a link, your contacts see your thought together with the moment that inspired it, in context, allowing you to share the experience of being there," says the web site.

The add-on is similar to the Sidewiki extension for Chrome, which lets users post text comments in a sidebar to any website. But Glass lets you anchor a comment, photo or video to any text or image anywhere on the page. Basically, it's as if someone placed a transparency over the website you're viewing and handed you a felt marker.

Users direct their posts, or "slides," to specific friends, who then see the action in a stream of their Glass contacts that can be pulled up within the browser. Click the update and zoom to the website with your friend's comment, exactly as it appeared to them, and comment back, add a photo or invite more friends to join the conversation. Your stream lives in your browser but may also be accessed from the Glass web site.

The result is a visual discussion that could end up feeling more immediate and more social than copying a link, heading over to Twitter and trying to make a coherent remark in however many characters you have left.

One of the most interesting things that struck us was how unwebby the idea is. You don't interact with the page, just with your friends. This app seems like an especially good fit for the visual, stripped-down interface and immediate feedback on a device like the iPad. It's also well-suited to collaborations where multiple users need to talk about a project unambiguously.

Glass's catchphrase is, "Share experiences, not content," which gets to the heart of why this app just might be as sticky as a Post-It note. Perhaps the new frontier of the social web will be obscuring all the computers, connections, apps and tools between you and your friends.