The Flash file is taken from Designhulp. You can find it here.
Alternative content. Google and screen readers would read these lines.
Note that I didn't use a Flash sniffer yet. This is only a test if it is possible to embed Flash using JavaScript.
function createFlashMarkup(width,height,uri,replaceid){
var embed = document.createElement('embed');
embed.setAttribute('width',width);
embed.setAttribute('height',height);
embed.setAttribute('src',uri);
var div = document.getElementById(replaceid);
document.getElementById('body').replaceChild(embed,div);
}
window.onload = function(){
createFlashMarkup('550','400','vuurwerk.swf','replaced-by-flash');
}