evert

// ==UserScript==
// @name           Referral: your mom
// @namespace      yourmom
// @description    This script changes every utm_source variable in links to 'Your mom'.
// @include        *
// ==/UserScript==

var links = document.getElementsByTagName('a');
for(var i=0; i<links.length; i++) {
   links[i].href = links[i].href.replace(/([&|?])utm_source=(.*)([&|?|^])/,"$1utm_source=Your+mom$3");