HatCloud is built in Ruby. It allows you to discover the real IP address of a host that is being hidden by CloudFlare.
This can be useful if you need test your server and website. obviously it can also be used for malicious purposes, but hey so can a car!
I know you guys are going to be responsible with this tool.
This tool is mainly for testing your protection against Ddos (Denial of Service) or Dos. (but hey you know your own server IP already, right??)
CloudFlare offers WAF, CDN services and distributed domain name server services. CloudFlare sits in between the visitor and the Cloudflare servers, acting as a reverse proxy for websites.
To use the tool simply type:-
ruby hatcloud.rb -b DOMAIN-NAME.COM-HERE
Being the responsible person I am here is a redacted screenshot, you get the idea.
Grab it from Github