A bunch of my sites have been getting hits from this part of Altavista. But when I tried to do a search on the regular Altavista with a keyword phrase I couldn't find my site. When I did the same search in listings.altavista.com I saw the site. The results in this database are different than that from just the regular www.altavista.com section.
If you do use the same keyword search phrase you should get different results.
Thinking about it, this seems to redirect to the site mention in this [webmasterworld.com] thread - ie when they were showing Goto results in green. So this must be the site where all the junk they have found is kept, and as you say, they whittle it down to the junk, I mean, ultra-relevant results that they show at www.