If you do any Silverlight or WPF/E work, you've likely run across a control named "AgHost" or the prefix "Ag" used in various places in the code(moreso in WPF/E). That naming looks like it is slowly going away in favor of using the full word "Silverlight", but the "Ag" prefix is still there in the javascript.

Ag is the symbol for Argentum, which is the old name for Silver.

Useless trivia, perhaps, but at least you won't be wondering about the naming any more :)