I was able to rack up a score of 1032 actual zerg kills (https://plus.google.com/u/0/105804947146425070365/posts/LKju...) using simulated mouse clicks on the zerglings. It's not that hard: https://gist.github.com/2514407 . There are relatively simple guards one could engineer into the zerg rush program to prevent simple hacks like this though, if one cared to. Fun stuff!