If you by mistake deleted the Windows “Show Desktop” shortcut icon in the QuickLunch, you can get it back by creating a text file named “Show Desktop.scf”, and drag it to the QuickLaunch.
This is the content of the “Show Desktop.scf” file, for Windows XP and Vista respectively.
Windows XP
[Shell]
Command=2
IconFile=explorer.exe,3
[Taskbar]
Command=ToggleDesktop
Windows Vista
[Shell]
Command=2
IconFile=shell32.dll,34
[Taskbar]
Command=ToggleDesktop

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