Any data type that can be handled as a string by JavaScript can be sent. Here are functions that will take strings for JavaScript code, CSS styles, and images and convert them into resources the browser can use:

handleImageData.js

function handleImageData(data, mimeType) {
 var img = document.createElement('img');
 img.src = 'data:' + mimeType + ';base64,' + data;
 return img;
}
function handleCss(data) {
 var style = document.createElement('style');
 style.type = 'text/css';
 var node = document.createTextNode(data);
 style.appendChild(node);
 document.getElementsByTagName('head')[0].appendChild(style);
}
function handleJavaScript(data) {
 eval(data);
}