So it's called Sitelinks ~ From Google

[AbsoluteKC]

Recently there has been questions asking why certain number 1 sites have include a set of links below them to pages within the site. Google called them sitelinks:

Our systems analyze the link structure of your site to find shortcuts that will save users time and allow them to quickly find the information they're looking for.

We only show Sitelinks for results when we think they'll be useful to the user. If the structure of your site doesn't allow our algorithms to find good Sitelinks, or we don't think that the Sitelinks for your site are relevant for the user's query, we won't show them.

At the moment, Sitelinks are completely automated.

Source: http://www.google.com/support/webmasters/bin/answer.py?answer=47334&topic=8523

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