git clone [email protected]:DTrejo/favicon.js.git
cd favicon.js
npm install

(npm install guide)

$ favicon google.com amazon.com github.com
http://google.com/favicon.ico
http://amazon.com/favicon.ico
http://github.com/favicon.ico

var favicon = require('favicon');
var icon = favicon.get('dtrejo.com', function(err, url){
  console.log(url);
});

Note that at the moment it will return http://dtrejo.com/favicon.png if it cannot find a given site’s favicon in any of the normal places.
I should probably change this.

favicon.js is a Javascript/node.js port of braveicon by bmelton.

Fetches a site’s favicon URL.  Respects link rel="" declarations

most importantly, per W3C spec, however, it favors ‘shortcut icon’

over /favicon.ico, as many software packages explicitly declare

via shortcut icon, and W3C snubs /favicon.ico, generally speaking