Bing.com is a search engine owned by Microsoft formerly known as MSN Search and Live Search. It offers the unique feature to search for websites by IP address. Bing-ip2hosts leverages this to enumerate all host names that Bing has indexed for any given IP address.
Bing-ip2hosts is written in the Bash scripting language for Linux. This was first published in 2009 and released at the Kiwicon conference in New Zealand.
Unlike many other subdomain enumeration tools, this does not require an API key. Originally this project used the mobile interface but now uses the regular web interface.
bing-ip2hosts (o.4) by Andrew Horton aka urbanadventurer