Look at http://www.google.com/webmasters/+1/button/ for instructions on adding the Google +1 button to posts on your web site. Supposedly this will result in improved ranking in Google’s search engine.
The actual code you insert at the end of your page is:
<!-- Place this tag after the last plusone tag -->
<script type="text/javascript">// <![CDATA[
(function() {
var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true;
po.src = 'https://apis.google.com/js/plusone.js';
var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s);
})();
// ]]></script>
And you place this code:
<!-- Place this tag where you want the +1 button to render -->
<g:plusone></g:plusone>
everywhere you want a +1 tag to appear.