I've got a site that's using the Google CDN to host the jQuery lib for us, done like this:
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery.min.js" type="text/javascript"></script>
Inconsistently, that file seems to be coming down the line in binary, not text. So when you access the file directly in the browser, you see weird characters, not the text from the JS code.
This of course breaks everything. It only seems to be happening in Firefox, Chrome was fine. I should note this code has been running fine for ages. We've only noticed this problem in the last hour.
I guess its possible Google is having issues at the moment?