Annotating online documentation

I had this great idea a while back; I would build a little app that let me put notes on any url on I hit and allow me to share those notes with others. Well, looks like a lot of people have beaten me too it. The initial idea was to apply the idea to MSDN‘s documentation, since much of it is missing interesting information. I just stumbled onto the MSDN Labs Annotations project, which seems to be doing just what I wanted. The scope seems to be limited to the Longhorn docs though, so maybe I still have a chance… There have to be other apps like this out there though; this is hardly an original idea. Maybe tomorrow I’ll spend some time googling for apps that do this already.