accept_fallthrough.js

var express = require('express')
  , app = express()

app.use(express.bodyParser());
app.use(express.methodOverride());
app.use(app.router);

// Freeze the route to /foo/static
app.get('/foo/static', function(req, res, next) {
  if (!req.accepts('html')) {
    /* do the thing */
    res.send('A thing');
  } else {
    /* fall through */
    next();
  }
});

// Everything else other than /foo/static is treated as a parameter
app.get('/foo/:id', function(req, res, next) {
  res.send(req.param('id'));
});


app.listen(3000);