sidebar anyone?

Has anyone seen a “ sidebar” or “ floater” for Firefox?

Using a lot, I like to fill in as much metadata as possible, which includes writing a fairly representative description of what I’m bookmarking. Since clicking on my bookmarklet effectively brings me to the posting page, I lose sight of the web page I’m on! I would seriously think that it would be more productive if there were a way to write my posts while still being able to see what I’m writing about. Share your finds in the comments!

P.S. The closest I found was this sidebar