gistfile1.js

var express = require('express');
var app = express();
var fs = require('fs');

app.use(function(req, res, next) {
  if (req.url.match(/^\/?[^/]+\/?$/)) {

    if (req.url.match(/[.][0-9a-z]+$/i)) {

      next();

    } else {

      if (!req.url.match(/\/$/)) {

        req.url = req.url+"/";

      }

      fs.stat(req.url.replace(/^\//,"")+"index.html",function(err,st) {

        if (err) res.redirect(req.url+"live_files/index.html");
        else res.redirect(req.url+"index.html");

      });

    }

  } else {
    next();
  }
});

app.use(express.static(__dirname));

app.listen(80);