Wiki Edit Icon
Edit Icon 
The icon is in the process of being determined by consensus among many prominent Wiki communities, as a means of "branding" the Wiki concept (similar in purpose to the icon used for RssFeeds). WikiWikiWeb started using it in June 2007. The discussion for the icon is being held at http://universaleditbutton.org/Universal_Edit_Button.
See: EditText, UniversalWikiEditButton