http://h34nug3iwqjf2376fmmzdhgqivckzemcujmarlptfqeqtq7vya47yyad.onion/2006/12/30/websec-monitor-websites-for-changes/index.html
When you want to monitor changes to such sites, you can only visit it from time to time, or use public services such as FEED43 or RSSPECT . Websec (Web Secretary) automates the process of regularly visiting the website: it typically runs in a cron job , and compares the content of a web page with what it fetched during the previous run.