with the following script, WinKey+1 shall toggle: 

    #1::Run %A_AppData%\Microsoft\Internet Explorer\Quick Launch\Show Desktop.scf



Show Desktop.scf:

    [Shell]
    Command=2
    IconFile=explorer.exe,3
    [Taskbar]
    Command=ToggleDesktop


And THIS is how you figure out which order they're in:

    http://www.autohotkey.com/forum/topic46454.html
    (specifically, the last parameter from 'FileGetShortcut')

And I *think* this does the Windows+1, Windows+2, etc code already:

    http://www.autohotkey.com/forum/topic46454.html