随机滚动图片，刚好碰到的，看看是不是符合你的要求，代码如下：
－－－－－－－－－－－－－－－－－－－－－－－－－－－－－－－－－－
1<html>
2<head>
3<meta content="text/html; charset=utf-8" http-equiv="Content-Type"/>
4<title>随机滚动图片</title>
5</head>
6<body>
7<div id="img" style="position:absolute;z-index:99;">
8<img border="0" onclick="pause_resume();" src="http://expert.csdn.net/images/csdn.gif"/>
9</div>
10<script language="JavaScript">
11<!-- Begin
12var xPos = document.body.clientWidth-20;
13var yPos = document.body.clientHeight/2;
14var step = 1;
15var delay = 5;
16var height = 0;
17var Hoffset = 0;
18var Woffset = 0;
19var yon = 0;
20var xon = 0;
21var pause = true;
22var interval;
23img.style.top = yPos;
24function changePos() {
25width = document.body.clientWidth;
26height = document.body.clientHeight;
27Hoffset = img.offsetHeight;
28Woffset = img.offsetWidth;
29img.style.left = xPos + document.body.scrollLeft;
30img.style.top = yPos + document.body.scrollTop;
31if (yon) {
32yPos = yPos + step;
33}else {
34yPos = yPos - step;
35}
36if (yPos < 0) {
37yon = 1;
38yPos = 0;
39}
40if (yPos >= (height - Hoffset)) {
41yon = 0;
42yPos = (height - Hoffset);
43}
44if (xon) {
45xPos = xPos + step;
46}else {
47xPos = xPos - step;
48}
49if (xPos < 0) {
50xon = 1;
51xPos = 0;
52}
53if (xPos >= (width - Woffset)) {
54xon = 0;
55xPos = (width - Woffset);
56}
57}
58
59function start() {
60img.visibility = "visible";
61interval = setInterval('changePos()', delay);
62}
63function pause_resume() {
64if(pause) {
65clearInterval(interval);
66pause = false;
67}else {
68interval = setInterval('changePos()',delay);
69pause = true;
70}
71}
72start();
73// End -->
74</script>
75</body>
76</html>