valeyard - 1:36 pm on Oct 8, 2004 (gmt 0)

The obvious theory is that "client=" is a flag Google uses for something other than a browser type.

At a quick look, adding "client=1" seems to return approximately the same number of results as using Safesearch.

Guess: perhaps "client=whatever" refers to queries coming from third parties using Google as a back-end? Google is filtering the results to avoid offending their user base.