A little node server that just gives your request back to you as JSON.

echo.js

var http = require('http')
  , sys = require('sys')
  , server
  ;

server = http.createServer(function(req, res) {
  var echo = {}
    ;

  echo.headers = JSON.stringify(req.headers, true, 2);
  echo.body = res;

  //console.log(echo);

  res.writeHead(200, { 'Content-Type': 'application/json' });
  res.write(echo.headers);
  req.pipe(echo.body);
});
server.listen(3030);