Just as Alan showed how you can use the “New” toolbar to have any document added to that drop down you can also use it for any bookmark.
For instance, I have my blog entry in that list so I can do a single click to add an entry to my blog – which is strictly web based. The “Open” list is a supported drop target for any URL – from Internet Explorer or FireFox. So when you click on the button entry it launches the web browser to that URL.
The only issue I have is the button is only updated at the start of Notes so you will have to restart Notes if you add them like Alan showed.