The ad copy reads "directNIC features a revolutionary domain search feature called Linguatron which allows the directNIC user to enter a search query and browse a list of available domains that are conceptually related to the search term"
I didn't notice too much "conceptually related" but it was quick about telling me what is and is not available and provides a laundry list of similar names. Check it out at [directnic.com...]
There are quite a few of these "services" around at the moment. What they do is simply prefix or suffix additional words to your stock word to give you a few choices.
You could also try Domain Name Anaylzer from [softnik.org ] which does the same thing and then queries Whois for available domains. The good thing about DNA is you can build your own lsts of prefixes and suffixes.
One of the best online services I saw actually queried the GOTO Search Suggestion tool based on your stock word and then built available domains based on the most searched phrases. Clever.
Softnik DNA is great but.. be careful how many characters you include in the name, DNA won't warn you if you include too many, it just says 'available'. At least that's what it did last time I used it.