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WindowIconSizeMBI is a Mac menu bar application to set the icon size of either all or front most Finder window from the menu bar.
(There is a similar control on Mac OS 10.6 Finder windows; but this is different.)
To use: Install and run the application. Click on the menu bar icon for WindowIconSizeMBI to display its menu.
System requirements: Mac OS X 10.5 and above.