Graph is a type of hash that outputs in graphviz's dot format. It comes with a command-line interface that is easily pluggable. It ships with plugins to graph dependencies and status of installed rubygems, rake tasks, homebrew ports, mac ports, and freebsd ports, coloring leaf nodes blue, outdated nodes red, and outdated leaf nodes purple (red+blue). OSX quick tip: % sudo gem install graph --development % sudo brew install graphviz % gem unpack graph % cd graph* % rake gallery % open gallery/*.png