I'm in Chrome.
(Thanks to TIM for the quick lesson on browser console hacking)

For an auto-clicker, I like this one:
http://sourceforge.net/projects/hf-auto-clicker/

The game:
http://magicaweb.com/zoo/


Open the console, and type: 
 
setInterval(function(){for(var i=0;i<1;i++){IZGame.Zoo.money = 999999999999999;}}, 1000); 
 setInterval(function(){for(var i=0;i<1;i++){IZGame.Zoo.money = 1000000000000000000;}}, 10); <-- that's better

This gives you a jillion bucks, every second.

Then  enter this: 
 
IZGame.Zoo.priceIncrement = 0

This disables price increases when you buy stuff. birth rate and death rate, and changes the price to zero.
Get your birth rate to 100% and death rate to 0% with an autoclicker.