app.js

var express = require('express');
var load	= require('express-load');
var routes	= require('./routes');
var user = require('./routes/user'); //Chamou o routes/user aqui

var app = express();

app.set('views', __dirname + '/views');
app.set('views engine', 'ejs');
app.use(express.static(__dirname + '/public'));

app.get('/', routes.index);
app.get('/usuarios', user.index);
app.get('/usuarios/biografia', user.biografia);

load('models')
	.then('controllers')
	.then('routes')
	.into(app);

app.listen(3000, function () {
	console.log('Ntalk no ar.');
});

user.js

/*
* routes/user.js
*/
exports.index = function(req, res){
  res.send('user::index');
}

exports.biografia = function(req, res){
  res. send('user::biografia');
}