A lean typeahead library. Single file. Less then 400 lines of code.
It is a continuation of bootstrap-typeahead.js by Twitter.
Currently it needs jQuery. This dependency should be removed at some point.
Country: <input name=country type=text>
<script>
$('input[name=country]').typeahead({source: keyPress});
function keyPress(query,process)
{
process(['Andorra','Argentina','Australia',...]);
}
</script>