You can explore related site
names by slightly changing an existing site name. For example,
if you find a site name has a fourth-level or higher domain
name, you can try removing the left-most parts to see
if there are related sites, as in:
www.main.twenty.net ---> www.twenty.net
If a site name includes a number, you can try related
numbers. For example, you can change
www3.twenty.net ---> www2.twenty.net
Similarly, you can change:
www.twenty.net/news/story1.html --->
www.twenty.net/news/story2.html
You can also change the site suffixes to explore
related sites. Sometimes there are related sites, sometimes they
are owned
by the same company, and sometimes there isn't anything there.
For example, you can try each of the following sites:
www.time.com
www.time.org
www.time.net
You can also try different prefixes, such as "ftp" and "support" in
place of "www" to find sub-sites.