As some might know already styling select element is a nightmare, literally impossible without some javascript trickery. The new datalist in HTML5 could serve the same purpose s
HTML:
Input - Datalist
jQuery:
var result='';
$(document).ready(function(){
$('input[type=text]').focus(function(){
$('#categories option').each(function(){
result=result+" "+$(this).val();
});
$('#result').show().html(result);
$('input[type=text]').unbind('focus');
});
$('input[type=text]').blur(function(){
$('#result').hide();
$('input[type=text]').focus(function(){
$('#result').show();
});
});
});
Working JS bin
http://jsbin.com/urupit/4/watch