Google Operating System: Stylish New Design in Google Notebook
Google Notebook is a very useful tool for research, at least that is how I use it ;o)
Like all Google services, you can use your Gmail account to access your Notebook, take a small tour
Now, NoteBook is out of beta with a nice AJAX interface. After you download the Notebook plug-in into your browser, left-click any selected text and select "Note This" it will be added to your Notebook.