Simple bot for CookieClicker: http://orteil.dashnet.org/cookieclicker/ How to use: Paste the following into the JavaScript console in your browser and run it. To start the bot type: "CookieClicker.start();" to stop it do: "CookieClicker.stop();" (or just reload the page).

cookiebot.js

CookieClicker = {
	start: function() {
		this.clickInterval = setInterval(function(){
			// Click the large cookie as fast as possible!
			document.getElementById("bigCookie").click();
		}, 1);

		this.goldInterval = setInterval(function(){
			// Click the golden cookie
			var shimmer = document.getElementsByClassName("shimmer")[0];
			if (shimmer) {
				shimmer.click();
			}
		}, 1000);
	},
	stop: function() {
		clearInterval(this.clickInterval);
		clearInterval(this.goldInterval);
	}
};
UpgradeClicker = {
	start: function() {
		this.buyInterval = setInterval(function(){
			// Now we need to buy stuff with our money.
			// Then try to buy the most expensive upgrade
			var upgrade = [].slice.call(document.querySelectorAll(".upgrade.enabled")).reverse()[0];
			if (upgrade) {
				upgrade.click();
			} else {
				// Then try to buy the most-expensive item
				var last = [].slice.call(document.querySelectorAll(".product.enabled")).reverse()[0];
				if (last) {
					last.click();
				}
			}
		}, 10000);
	},
	stop: function() {
		clearInterval(this.buyInterval);
	}
};

I prefer "delta cps per cookie". In the beginning buying a cursor gives you 0.1 cps for 15 cookies, that is, about 6.67 mcps/c, and hiring a grandma gives you 0.5 cps for 100 cookies, that is, 5 mcps/c, which makes cursor more effective. But as soon as you have 3 cursors, buying one more cursor costs you 22.8 cookies, which makes its efficiency below 5 mcps/c (4.38 mcps/c to be a bit more exact), which justifies waiting for 100 cookies in bank to hire a grandma rather than to spend all your income on cheap and ineffective labour force.

@iconmaster5326 & @ob-ivan great points! I look forward to your forks ;-)

https://gist.github.com/ob-ivan/6800011 -- something like that, I suppose.

Try this one. Made it recently in a contest against friends.
https://github.com/DevL0rd/Cookie-Clicker-Bot