// ==UserScript==
// @name           Autoscroll
// @namespace      https://gist.github.com/
// @description    Scrolls the page automatically
// @include        http*://*
// @version        1.0
// ==/UserScript==

var interval;

GM_registerMenuCommand("Start Autoscroll", function () {
	var speed = prompt("Select speed (10 fast, 2000 slow)", "100");
  interval = setInterval(function () {
    window.scrollBy(0, 1);
  }, speed);
});

GM_registerMenuCommand("Stop Autoscroll", function () {
  try {
    clearInterval(interval);
  } catch () {}
});