https://github.com/mscdex/busboy/issues/92

busboy-memory-test.js

var http = require('http');
var fs = require('fs');
var Busboy = require('busboy');
var PORT = 6666;

http.createServer(function(req, res) {
  if (req.url === '/') {
    res.writeHead(200, {'content-type': 'text/html'});
    res.end('<form action="/upload" enctype="multipart/form-data" method="post">'+
              '<input type="file" name="upload" multiple="multiple" onchange="this.parentNode.submit()">'+
            '</form>');
  } else if (req.url === '/upload') {
    var busboy = new Busboy({headers: req.headers});
    busboy.on('file', function(_, file) {
      file.pipe(fs.createWriteStream(__dirname + '/upload'));
    });
    busboy.on('finish', function() {
      res.writeHead(200, {'Connection': 'close'});
      res.end("That's all folks!");
    });
    req.pipe(busboy);
  }
}).listen(PORT, function() {
  console.info('listening on http://0.0.0.0:' + PORT + '/');
});