Lately I've been tracking a spammer on craigslist. I recently discovered that he's added a new technique to his arsenal, he registered a whole bunch of domain names but they all resolve to the same ip address.
Is there any way to take an ip address and get a list of all the domain names that resolve to that ip?
Oh, actually you can. After all, if there are companies constantly indexing the whole www, or even making a "backup" of it, why wouldn't be possible to index information about domains and IPs?
There are some free services that do that: You provide a public IP address, and you get a list with the domain names that resolve to it.
This can be quite useful for several purposes. Tracking a spammer seems to be one of them.
I don't know how accurate, current or complete is the information that these services provide, but they have helped me in dealing with situations like the one you described.