gistfile1.js

var fs = require ('fs'),
  async = require ('async');


var q = async.queue(function (task, callback){
	fs.appendFile('UIDs.txt', task.value + '\n', function (err) {
		callback();
	});
}, 250);

for (i = 73589; i <= 1972100; i++) {
	q.push({'value' : i}, function (err) {});		
}