Thor is a simple and efficient tool for building self-documenting command line utilities. It removes the pain of parsing command line options, writing "USAGE:" banners, and can also be used as an alternative to the Rake build tool. The syntax is Rake-like, so it should be familiar to most Rake users. Please note: Thor, by design, is a system tool created to allow seamless file and url access, which should not receive application user input. It relies on open-uri, which combined with application user input would provide a command injection attack vector.