cron is failing to run my AppleScript
Cron has be deprecated on modern versions of OS X. Apple's suggestion is to use launchd instead. You will find Lingon to be a useful tool for creating launchd daemons. 

If you would prefer to use iCal to launch the script, you can create a separate calendar for scripted event(s), and hide it from view. It will function, but your calendar view will not be cluttered.