Snakeskin

Demo

HTML

<script src="http://kobezzza.com/files/snakeskin.beta.min.js"></script>
<script type="text/x-snakeskin-template" id="templates">
    {template helloWorld(name = 'world')}
        <p>Hello {{user}}! You have
            <strong>{{messages.unread}} new messages</strong>.
        </p>
    {/}
</script>

<div id="test"></div>

JavaScript

Snakeskin.compile(document.getElementById('templates'));
document.getElementById('test').innerHTML = helloWorld();