Songza is simple music serach tool. It’s intended as a user interface showcase so there’s some fancy Javascript and CSS going on. External JS and CSS files are loaded through a wrapper:

<link rel="stylesheet" type="text/css" 
    href="/c/?files=css/songza.css,css/flower.css,css/thickbox.css,css/humanmsg.css" />

Each of the CSS files exists on the server seperately, but the c script concatenates them all together before sending to the server. It also seems to strip out whitepsace (but doesn’t gzip them).

It’s a clever idea - they are using over a dozen external files so there’s a big saving in reducing the number of HTTP requests.