<style type="text/css" media="all">
select {width: 100px;}
</style>
<script type="text/javascript">
window.onload = function(){
document.body.appendChild(document.createElement('select'));
for(var i=0; i<10; i++){
var option = document.createElement('option');
option.style.background = '#'+i+i+i+i+i+i;
document.getElementsByTagName('select')[0].appendChild(option);
}
};
</script>