How/Why sublinks in Google
 

Does anyone know why certain sites get extra sublinks listed in google ?

An example is for Penisbot.com when you search for "porn links"

Wow, seems nobody knows!

Google considers it an "authority site"
Google also does something called "host crowding" when an index page is indented and replaced by a another inside page from the same site

Thanks T Pat

I see now why they are an 'Authority site' for the term 'porn links' but not for other terms. It is all the deep linking using that particular anchor text....very interesting.