Chew-and-Spit is a project mainly written in Ruby, it's free.
A Source code documentation tool written in Ruby
The problem with working on large systems is that they can grow from a handful of file to a tangled mess of codes some of which are likely to end up getting lost and forgotten leading to unnecessary code duplication.
Chew and Spit is my attempt to get a handle on that complexity by automating the profiling of large codebases. It's likely possible that a number of similar tools already exists, but I'm taking this as an opportunity to get some mileage on ruby (been reading the Dave Thomas' pickaxe book while working on this early on) while also taking on the problem of 'how to tackle large systems' (As a developer, this been a constant source of both annoyance and pain and I'm compelled to find a means around this).
Chew and Spit is designed to be extensible so it won't just be working on one system but (potentially) on a variety of systems/languages. It is limited to PHP support at the moment, but support for other languages will be thrown in, gradually.
rghost ruby-graphviz
$ spit.rb <outputfile.pdf>