Looking for DNS reverse lookup service

[Robert Lowe]

Humes, David G. wrote:

> I realize there's no authoritative way to provide all the domain names
> associated with an IP address, and that any service that claims to have this
> capability is doing it by mining data, and will never be fully accurrate.
> But, having said that, here's why it would be valuable.  Let's say that
> you've determined that the host at IP x.y.z.q is sending exploit code to
> hosts in your network.  You're pretty certain that it's not a spoofed IP, so
> you say let's block the IP at the firewall.  Several minutes later when the
> phones start ringing, you find that you've just blocked access to google,
> Symantec and who knows what else.
> 
> The service that I saw showed you 4 domain names for an IP for free, and if
> you wanted to see them all, you had to sign up.  

http://www.nameintelligence.com/

It references the site Ketil pointed to under WhoisAPI.  Three names for free...

-Robert