One solution I've used for storing small templates in HTML: http://ejohn.org/blog/javascript-micro-templating/

  <script type="text/html" id="user_tmpl">
    <% for ( var i = 0; i < users.length; i++ ) { %>
      <li><a href="<%=users[i].url%>"><%=users[i].name%></a></li>
    <% } %>
  </script>

Quick tip: Embedding scripts in your page that have a unknown content-type (such is the case here - the browser doesn't know how to execute a text/html script) are simply ignored by the browser - and by search engines and screenreaders.

This is quick and dirty, but much more elegant than writing HTML in JS.