Google Sidewiki, allows you to contribute helpful information next to any webpage. Google Sidewiki appears as a browser sidebar, where you can read and write entries along the side of the page. Sidewiki is released as part of Google Toolbar for Firefox and Internet Explorer, and will available in Google Chrome and elsewhere soon. Also an API is released to let anyone work freely with the content that's created in Sidewiki. Just visit google.com/sidewiki to download Google Toolbar with Sidewiki and contribute your own entries alongside pages on the web.