Crystal Clear theme for ShapeShifter is an ongoing experiment in transparency for the Mac OS X user interface. By utilizing a customized open-source Cocoa plugin called SetAlphaValue, it's quite possible to enable fully (well, almost fully) transparent toolbars, buttons, and menubars in Mac windows without introducing undue confusion about which window you're working with. For the full background, including a list of usage tips and known issues, please refer to Crystal Clear: Pushing Mac OS X Windows Beyond Translucent from February 2007, or the latest article, Crystal Clear 1.1: More Refinements, Plus 109 New 'Crystal Albook' Icons.
Crystal Clear includes modified elements for the following applications: Automator, DevonThink Pro, FontBook, iCal, iTunes, Mail, Preview, QuickTime Player, Safari, System Preferences, ThemePark, and Yummy FTP.
SetAlphaValue - Also in the folder is a custom installation package for SetAlphaValue, which is needed to enable full transparency in many Mac OS X application windows. Simply doubleclick on the SetAlphaValue4CC.pkg file, and you will be guided through the steps necessary to install this software. (Note: If you have previously installed SetAlphaValue, you don't need to reinstall it. The version bundled with Crystal Clear 1.1 is the same as that in version 1.0.)