bar.js

module.exports = {
    bar: function() {
        return 'Return from bar::bar()'
    }
}

config.js

module.exports = {
    foo: 'bar'
}

foo.js

var bar = require('./bar');

module.exports = {
    foo: function() {
        return 'FOO from ./lib :: ' + bar.bar();
    }
}

response.txt

Hello World
App (davglass) is running (28306)
FOO from ./lib :: Return from bar::bar()
Config::foo: bar

server.js

require.paths.push('./lib');
var foo = require('foo.js');


var config = require('./config');

console.log(config);

var app = require('http').createServer(function(req, res) {
    res.writeHead(200, {'Content-Type': 'text/html'});
    res.end('Hello World<br>App (davglass) is running (' + process.pid + ')<br>' + foo.foo() + '<br>Config::foo: ' + config.foo);
});

app.listen(5000);