Bookmarklet to import fartscroll.js (imports jquery 1.9.1 if cant find jQuery).

gistfile1.js

(function(){
    var a = function(){
        var y = document.createElement('script');
        y.onload = function(){ jQuery(document).fartscroll(600) };
        y.src="https://raw.github.com/theonion/fartscroll.js/master/fartscroll.js";
        document.head.appendChild(y);
    };
    if(typeof jQuery == 'undefined') {
        var x = document.createElement('script');
        x.onload = a;
        x.src="https://ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js";
        document.head.appendChild(x);
    } else {
        a();
    }    
})();

/*
Minified:
(function(){var e=function(){var e=document.createElement("script");e.onload=function(){jQuery(document).fartscroll(600)};e.src="https://raw.github.com/theonion/fartscroll.js/master/fartscroll.js";document.head.appendChild(e)};if(typeof jQuery=="undefined"){var t=document.createElement("script");t.onload=e;t.src="https://ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js";document.head.appendChild(t)}else{e()}})()
*/

Fixed to import jQuery when needed

Weird behavior using $. Switch to jQuery