When you search for a particular keyword, some websites have a list of additional pages indexed/displayed in search results?
how can this be acheived... technically.

Example:
Search for keyword microsoft displays:

Microsoft Corporation
The entry page to Microsoft's Web site. Find software, solutions, answers, support, and Microsoft news.
www.microsoft.com/ - 31k - 8 Oct 2006 - Cached - Similar pages

Download Center - www.microsoft.com/downloads/
Windows Family - www.microsoft.com/windows/
Office Online - office.microsoft.com/
Support - support.microsoft.com/
More results from www.microsoft.com »

?