If you want a script or an application to launch at a predetermined time, use an iCal alarm will do the trick.

  1. Create an appointment for the time you want to launch the app and then choose the “Open file” as the alarm option.
  2. Select the application or script from the popup menu or select “Other…” and navigate to file to choose it.

The application or script will be launched at the scheduled time, or, if the computer is off or asleep, the application or script will launch the next time you log on or the computer wakes up.