I'm not sure if this submission will count, but I, unfortunately, didn't have time to work on a project specifically for this challenge. I did, however, write a program we use internally to perform repetitive tasks on a specified interval in less than a week.
The app, dubbed Marvin, looks to several tables in a database for lists of tasks with specified intervals ranging from "constant" to "monthly." It then evaluates the record's other parameters to decide if it will run the task. At it's core is a timer that fires a method to find processes loop through them and perform logic for each task. The timer period is set to 60 seconds. The app then writes a record to a log indicating if it ran, errored or neither, the time and the id of the process. Below are some screenshots. I wish I could share the project but it would be nearly useless if I stripped out privileged information...and @Bill K would kill me. I would be happy to give a quick demo or record a demo video if that would help.
As you can see it's still fairly new with only one live process and a few test processes, but it is only 4 days old.
The processes table: