Shoutbox

if the image is an <img> tag, something like this might work:

code:

---

<input onclick="getimage()">

<script>
function getimage() {
   document.getElementById(picture id name).src = 'path to random image generator php file'
}
</script>

---

If its a css background image, use something like this:

code:

---

<script>
function getimage() {
   document.getElementById(picture id name).className = 'path to random image php file'
}
</script>

<script>
function getimage() {
   document.body.style.backgroundImage = 'url(path to random image php file)'
}
</script>

---