heres a bookmarklet for selecting and showing the base 64 encoded image in another popup window... tried on opera
javascript:(function(){var str=""+(window.getSelection?window.getSelection():document.getSelection?document.getSelection():document.selection.createRange().text);if(!str) str=prompt("input text:", "");if(str!==null) msgWindow=window.open("","","location=yes,status=yes,menubar=yes,scrollbars=yes,resizable=yes,width=547,height=442");msgWindow.document.write("<html><HEAD><title>b64_image</title><SCRIPT LANGUAGE='JavaScript'></SCRIPT></HEAD><body><img name=img1 src='data:image/jpg;base64,"+str+"' alt='Base64 encoded image' onclick='close();' width='' height=''/></body></html>");msgWindow.document.reload})();
MHTML is also an actual standard ("MIME-encoded HTML"), it's just that Firefox and Opera implemented this crappy excuse for it and didn't do MHTML.
Hmm...interesting.
Actually, it's supposed to work in just about all modern browsers besides IE. I know that it works in Opera, and I think that it does in Safari/KHTML/WebKit as well. It's an actual standard--there's even an RFC: http://www.ietf.org/rfc/rfc2397.txt
Whoa! One feature where it's actually Firefox and Opera that fumble instead of IE. This is embedded images for browsers that are too pansy to tackle MHTML.
Ah come on. Lots of people use data urls.
In Greasemonkey (which is heavily sandboxed and prevented from causing general havoc) you can fire-up a spreadsheat with a url like:
data:application/vnd.ms-excel;base64,YQliCWMKZAllCWY=
data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABEAAAAECAIAAADnFEOFAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAgY0hSTQAAeiYAAICEAAD6AAAAgOgAAHUwAADqYAAAOpgAABdwnLpRPAAAAIBJREFUGFddT0sOhSAQI/wJBPH+l0SICaDIq87uzWJS2k4bmFLKe38cx1rLOXddF2PseR48Aay1YAhrrXvvAO/knI0xJPztMUZrjXMOvpSCDcy2bSMfsvd9h4MwUtEQQiB1zhljrLXe9/324AwyWKpNKZ3n+eZ9QzdCCHwBHinlD4upYDGkEezaAAAAAElFTkSuQmCC
heh cool.