Take it like a gift
brutesubs
Automation framework for running multiple open sourced subdomain bruteforcing tools in parallel.
Burp Suite
The class-leading vulnerability scanning, penetration testing, and web app security platform.
Infection Monkey
Test a data center's resiliency to perimeter breaches and internal server infection.
hakip2host
Takes a list of IP addresses then does a series of checks to return associated domain names.