function displayRandomImage(indexNum){
	if (!document.getElementById || !document.getElementsByTagName || !document.createElement) {
		alert("Probelm with JavaScript, you need a new browser!");
		return;
	 } else {
	 	var tmpImage;
		tmpRndmNumber = Math.round(Math.random()*(imageArr.length - 1));
		rndmNumber = tmpRndmNumber;
		var foo = document.getElementById('topImage');  // safe to use
		var fooToo = document.getElementById('captionText');
		foo.style.backgroundImage = imageArr[indexNum];
		if (foo.childNodes.length > 1){ // For Mozilla Based
			fooToo.childNodes[0].nodeValue = captionArr[indexNum];
			fooToo.attributes[1].nodeValue = linkArr[indexNum];
		} else { // for IE, thanks micro-sucks!
			fooToo.innerText = captionArr[indexNum];
			fooToo.href = linkArr[indexNum];
		}
	 }
}