Transform Google Docs into a Mac OS X Leopard app. The buttons are modeled after the leopard Finder toolbar buttons, as are the toolbars. All menus and contextual (right-click) menus are themed to look like the native Mac OS X menus. This theme also styles Google Docs' DHTML windows to match the actual window chrome from OS X, adding shadows, status bars, lighting and cursor modifications to complete the effect - the two types of windows should look identical after enabling this theme.

This is what the main Google Docs UI looks like with this theme:
http://jasonmillerdesign.com/images/editor-uploads/Google_Docs_Mac_OSX_Theme_5.png

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http://jasonmillerdesign.com/Free_Stuff/Google_Docs_Mac_OS_X_Leopard_Theme