comment_form.xjs.html

<element name="comment-form" constructor="CommentForm">
  
  <template>
    <form class="commentForm" onSubmit={this.handleSubmit}>
      <input type="text" placeholder="Your name" ref="author" />
      <input
        type="text"
        placeholder="Say something..."
        ref="text"
      />
    </form>
  </template>
  
  <script>
    CommentForm.prototype.handleSubmit = function(){
      var author = this.refs.author.getDOMNode().value.trim();
      var text = this.refs.text.getDOMNode().value.trim();
      if (!text || !author) {
        return;
      }
      // TODO: send request to the server
      this.refs.author.getDOMNode().value = '';
      this.refs.text.getDOMNode().value = '';
    }
  </script>
  
</element>

timer.xjs.html

<element name="timer" constructor="Timer">
  
  <template>
    <div>Seconds Elapsed: {{this.state.secondsElapsed}}</div>
  </template>
  
  <script>
    Timer = React.createClass({
      getInitialState: function() {
        return {secondsElapsed: 0};
      },
      tick: function() {
        this.setState({secondsElapsed: this.state.secondsElapsed + 1});
      },
      componentDidMount: function() {
        setInterval(this.tick.bind(this), 1000);
      }
    });
  </script>
  
</element>

Cf. http://html5-demos.appspot.com/static/webcomponents/index.html#62