In modern browsers select options can now be style using most css properties. Of course, IE is still behind but it does support some styling as well. There are a lot more options on the site.
function setposition() {
algset = new Array('left', 'right', 'center');
sel=document.getElementById('theselect');
sel.style.backgroundColor='blue';
sel.style.textAlign='center';
sel.style.color='orange';
for (i=0;
i