Return URL Paramater Value

gistfile1.js

/* Returns URL parameter
 * url: http://www.somesite.com?name=hello&id=11111
 * z = gup('name'); // z = hello; s = string, or leave blank to target window location
 * Original code from Netlobo.com (http://www.netlobo.com/url_query_string_javascript.html)
 */
function gup(n,s){
 n = n.replace(/[\[]/,"\\[").replace(/[\]]/,"\\]");
 var p = (new RegExp("[\\?&]"+n+"=([^&#]*)")).exec(s || window.location.href);
 return (p===null) ? "" : p[1];
}

Thanks @sindresorhus! I've already found it useful! :)