In the Greek Orthodox religion, every day of the year is a nameday, dedicated to a saint or martyr. Each day has its associated feasts, celebrations, traditions, and so on, most ancient, and some actually predating Christianity, surviving from the days of Classical Greece. It's a lot to keep track of. Fortunately, modern technology once again helps maintain ancient tradition. Today Greek Calendar from Xarka Software displays all the Greek Orthodox namedays, feasts, and more, such as facts and lore from Greek history and culture ranging from antiquity to modern times. It has a lot of extras, too, such as extensive astronomical data. You can add your own dates, set countdowns to dates and events, and otherwise use it like any calendar or daybook.
Today's interface is a neat little expandable dialog affair that you can customize, resize, and relocate. Clicking on any of the thin tabs expands Today's contents. It has some particularly thoughtful options, such as latitude and longitude settings to guarantee accurate astronomical data. Of course, you can choose either English or Greek text. Another nice feature is the way it ties in with Windows email applications like Outlook and Outlook Express to help you celebrate namedays. It searches your Contacts folder and displays all your friends and relations with names that fall on certain namedays, so that you'll always remember to wish them "Hronia Polla."
Today Greek Calendar is free, but there's also a paid version that adds features like the ability to create and print custom calendars.