Javascript-bundler is a project mainly written in JavaScript, it's free.
Something to pack up packages in mootools package format
This is a (future) ruby-javascript for packing up javascript packages in mootools style.
Currently it holds examples of how it should work, to be translated into specs for implementation.
Conventions:
If a bundler is run with --with-dependencies option, then output directory is public/javascripts/packagename/Compiled instead of ./Source