Explanation    
/i/themes/theme_1/1px_trans.gif To the left you can see a Google Wave (only if you have an account).

Create a HTML Region with just a DIV:
<div id="wave" style="width: 560px; height: 420px"></div>

Add these lines to your Region Footer:
<script type="text/javascript" src="http://wave-api.appspot.com/public/embed.js">
</script>
<script type="text/javascript">
var wave = new WavePanel('https://wave.google.com/wave/');
wave.setUIConfig('white', 'black', 'Arial', '13px');
wave.loadWave('googlewave.com!w+2ORNCUPeP'); //This is the Wave ID
wave.init(document.getElementById('wave')); //This is the DIV
</script>
/i/themes/theme_1/1px_trans.gif
/i/themes/theme_1/1px_trans.gif /i/themes/theme_1/1px_trans.gif

nobody