UserJS: Check older version of websites with "Google cache"

Use this User JS:

Google_cache=function(){
var site=location.href.toString();
site=window.prompt('New url',site);
site=site.replace('http://','');
var url='http://webcache.googleusercontent.com/search?q=cache:' + site;
window.open(url, '_blank');
}

... and call this script with this shortcut or a mouse gesture:

Ctrl G=Enable javascript & Delay, 10 & Go to page,"javascript:Google_cache()"

Or use it as a bookmarklet:

  javascript:(function(){var site=location.href.toString();site=window.prompt('New url',site);site=site.replace('http://','');
var url='http://webcache.googleusercontent.com/search?q=cache:' + site;window.open(url, '_blank');})()