Auto scroll javascript

function getSize() {
    var myWidth = 0, myHeight = 0;
    if( typeof( window.innerWidth ) == 'number' ) {
        //Non-IE
        myWidth = window.innerWidth;
        myHeight = window.innerHeight;
    } else if( document.documentElement && ( document.documentElement.clientWidth || document.documentElement.clientHeight ) ) {
        //IE 6+ in 'standards compliant mode'
        myWidth = document.documentElement.clientWidth;
        myHeight = document.documentElement.clientHeight;
    } else if( document.body && ( document.body.clientWidth || document.body.clientHeight ) ) {
        //IE 4 compatible
        myWidth = document.body.clientWidth;
        myHeight = document.body.clientHeight;
    }
    return [myWidth, myHeight];
}
function pageScroll() {
    window.scrollBy(0,50); // horizontal and vertical scroll increments
    scrolldelay = setTimeout('pageScroll()',100); // scrolls every 100 milliseconds
}

function getScrollXY() {
    var scrOfX = 0, scrOfY = 0;
    if( typeof( window.pageYOffset ) == 'number' ) {
        //Netscape compliant
        scrOfY = window.pageYOffset;
        scrOfX = window.pageXOffset;
    } else if( document.body && ( document.body.scrollLeft || document.body.scrollTop ) ) {
        //DOM compliant
        scrOfY = document.body.scrollTop;
        scrOfX = document.body.scrollLeft;
    } else if( document.documentElement && ( document.documentElement.scrollLeft || document.documentElement.scrollTop ) ) {
        //IE6 standards compliant mode
        scrOfY = document.documentElement.scrollTop;
        scrOfX = document.documentElement.scrollLeft;
    }
    return [ scrOfX, scrOfY ];
}

function autoScroll() {
    w = getSize();
    p = getScrollXY();
    
    if (document.getElementById("banner")) {
        document.getElementById("banner").style.top = p[1] + w[1]/2 - 100 + "px";
        document.getElementById("banner").style.left = w[0] - 770 + "px";
    }
    delay = setTimeout('autoScroll()',100);
}