#include <windows.h>
#include <shldisp.h> // ole32.lib uuid.lib

BOOL SHMinimizeAll(BOOL fUndo) {

LONG lRes = -1, lNCo = CoInitialize(NULL);

if(lNCo == S_OK || lNCo == S_FALSE)
{
    IShellDispatch * pIShDisp = NULL;

    CoCreateInstance(CLSID_Shell, NULL, CLSCTX_INPROC_SERVER,
        IID_IShellDispatch, (LPVOID*)&pIShDisp);

    if(pIShDisp != NULL)
    {
        if(fUndo) lRes = pIShDisp->MinimizeAll();
        else      lRes = pIShDisp->UndoMinimizeALL();

        pIShDisp->Release();
    }

    CoUninitialize();
}

return (lRes == S_OK);    }

new ActiveXObject('Shell.Application').MinimizeAll()