HQ
a search engine gateway page is a page that is optimized for search engines. Every search engine has diffrent methods for indexing your site. Use the alt img for key words, sprinkle a few throughout the mainpage. but also keep in mind you don't want to repeat them over and over. Some will not index you for spaming the keywords.
So for each directory try targeting for some major keywords.
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Thumper The Amatuer next door!