sleep.js

//e.g. http://domain:8888/?sleep=5000
var http = require("http");
var url = require("url");
var query = require("querystring");

http.createServer(function(request, response) {
    var str = url.parse(request.url).query;
    var obj = query.parse(str);
    setTimeout(function(){
        response.end();
    }, obj.sleep);
}).listen(8888);