Js-preflight is a project mainly written in Ruby, it's free.
Easy preflight command-line script for jslint and jsmin
Run jslint and jsmin on all .js files sourced in html files provided as arguments. for details: preflight --help
Spidermonkey - brew install spidermonkey
Output isn't perfect yet; you'll need to move the packed .js file yourself for now
jsmin and jslint by the excellent Doug Crockford. Executable jslint provided by Andy Walker, see http://whereisandy.com/code/jslint/