Are there any valid uses for this that aren't cheating?
press squiggly linetype mousefire(1);[i mg]http://dumpfm.s3.amazonaws.com/images/20100930/1285886078018-dumpfm-shaq-1280210215398-dumpfm-uae-frog.gif[/img]
firing non-automatic guns, for example
Isn't that basically what you need, though? Pretty easy to type, you can cancel it by clicking.
If the weapon your game uses allows it to be spammed just with repeated clicking, the ball is really on your playing field.
So....firing a weapon at it's fastest possible rate with no effort from youSo....cheating
You mean like every semi-auto weapon ever?