AjaxWhois is similar to a site I wrote about a week ago called Instant Domain Search.
Ajaxwhois is similar to Instant Domain Search in that it has a nice Ajax interface. It’s has better functionality, though, because it pulls whois information directly into the results page and allow queries on top level domains beyond .com and .net (it even returned information for .name). While there is no link to register a domain (an easy addition), overall its a better tool for domain professionals.
From Steven Cohen.