Can be used as a tool to do 'batch' lookups of IP addresses, translating them to machine names. This can be very handy for processing web server logs. Also, the new version has a 'probing' feature by which it will query for DNS entries in a range of IP addresses (useful for testing a DNS, or for exploring a new network). Recently added features include greater flexibility in output format, and the ability to re-verify the validity of hostnames that are generated.