SyntaxHighlighter

<!-- Syntacs Hilighter -->
<link href='http://alexgorbatchev.com/pub/sh/current/styles/shCore.css' rel='stylesheet' type='text/css'/>
<script src='http://alexgorbatchev.com/pub/sh/current/scripts/shCore.js' type='text/javascript'/>
<link href='http://alexgorbatchev.com/pub/sh/current/styles/shThemeDefault.css' rel='stylesheet' type='text/css'/>
<script src='http://alexgorbatchev.com/pub/sh/current/scripts/shBrushPhp.js' type='text/javascript'/>
<script language='javascript' type='text/javascript'>
      // Bloggerの場合にコメントを外す
      //SyntaxHighlighter.config.bloggerMode = true;
      SyntaxHighlighter.all();
</script>
<!-- /Syntacs Hilighter -->

使い方

<pre class="brush: php">
function foo()
{
}
</pre>