a very little bit template engine （293 Bytes）
For example:
<!DOCTYPE html>
<html>
<head>
<title>JalonRender</title>
</head>
<body>
<div id="myBox"></div>
<script type="text/javascript" src="jalonrender.min.js"></script>
<script type="text/html" id="user_tmpl">
<h3><%=data.title %></h3>
<ul>
<% for(var i=0; i < data.list.length; i++ ) { %>
<li>
<span><%= data.list[i].text%></span>
<% if(data.list[i].done) { %>
<span style="color: red">√</span>
<% } else { %>
<span style="color: #ccc">☀</span>
<% } %>
</li>
<% } %>
</ul>
</script>
<script type="text/javascript">
var data = {
title: 'todo', list: [
{text: '去吃饭!', done: true},
{text: '去喝水!', done: false},
{text: '去打球!', done: false}
]
};
var myBox = document.getElementById('myBox');
myBox.innerHTML = render('user_tmpl', data);
</script>
</body>
</html>