side+wiki

Google's sidewiki is feature which installs an additional column on a webpage which allows you to post comments about the information on that page, to make notes for yourself and designed for public view. Website users can share information through the use of a sidewiki. The information posted by sidewiki users is uncensored and, therefore, the feature has been considered quite controversial. [|Google sidewiki]

However, some websites associated with it are unsecure at present and we don't recommend googling it in case something nasty happens to your computer!