The contoversial sitefinder service if anyones interested.
Although suspended for 404 redirects (and rightfully so) it stands
to reason Verisign would have one of the largest search
databases in the world (they do assign DNS domains after all).

In the two weeks it was used for .com and .net it was accessed
some 40 million times. I've had some great results, you might too.

http://sitefinder.verisign.com/index.jsp