Removing your URLs from Google

I seen one interested video in Youtube. Nobody wants to remove their URLs from Google. But in some exceptional reasons, we have remove the URL from Google. Some of the common methods can be used for removing URLs are

1. Dont link the page
2. editing the .htaccess
3. editing robots.txt
4. put noindex in the page (meta name="robots" content="noindex")
5. putting nofollow to the anchor tag (rel="nofollow")
6. Using URL removal tool (http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=61062)