Lingon

Lingon is a graphical user interface for creating an editing launchd configuration files for Mac OS X.

Lingon can start an app, a script or run a command automatically whenever you want it to. You can schedule it to run at a specific time, regularly or when something special happens.

Lingon can also make sure that an app or a script automatically restarts if it crashes. Lingon can do all this for you and much more.

Lingon X is based on the great Lingon 3 and eXtends it with new features like running jobs as root and at multiple dates. It is now even easier to use yet much more powerful.

Lingon lets you run things automatically by modifying configuration files for a built-in system function called launchd. So the system handles running the jobs so you don't need to have Lingon open after you have saved your job.