This is a project I have been working on for a while now. The alarm clock features a large 40×7 LED dot matrix display and a easy-to-use user interface for adjusting settings. The clock is controlled by an real time clock module that keeps track of date and time. The time of this module is set using a built in GPS every three seconds if the GPS has a valid position FIX. Read more about this project here: Arduino based GPS alarm clock