A simple web app

I want to create a simple web app. Here's the brief of the web app I want to create : This web app will make a visit to a link I provide and will override the http user-agent and the http referer. For link and http referer it should be configurable via a config file. And http user-agent is choosing random lines from mysql or from a file (which one is use the less server resource?). No need to create GUI. It's up to you if using frame or any other thing. As long as it works. PHP and Javascript preferred.