SwfObject

It's made us easier for validating/cleaning up HTML/XHTML codes and it's OO.

And a sample usage is:

<script type="text/javascript" src="swfobject.js"></script>

<div id="flashcontent">
This text is replaced by the Flash movie.
Or you can write:
"This content require flash version 8 ....and so on"
</div>

<script type="text/javascript">
var so = new SWFObject("movie.swf", "mymovie", "200", "100", "7", "#336699");
so.write("flashcontent");
</script>


<script type="text/javascript" src="ufo.js"></script>

<div id="ufoDemo">
<p>Replacement content</p>
</div>

<script type="text/javascript">
var FO = { movie:"swf/myMovie.swf", width:"300", height:"120",
majorversion:"6", build:"40" };
UFO.create(FO, "ufoDemo");
</script>