Your birthday is like your own personal holiday. Your friends and family gather to celebrate the joy that is you, and there are presents and cake - what's not to love? The only problem (blessing?) is that birthdays come but once every year.
There is a very valid method of doubling your celebration time, and no one can call you greedy, because it's technically a religious event. It's called a "name day", and it originated in the Roman Catholic and Greek Orthodox churches, where people would celebrate the feast day of the saint associated with their name.
Even in places where Protestant reformations outlawed Catholic activity, small pockets of Catholics still follow one calendar or another. Some countries even have secular name day calendars, still associated with saints' names.
Dissect Your Name
Even if your name isn't John, Luke, Mary, or another obviously biblical name, you may be able to trace it's cultural roots back to a saint. Carmen, for example, is a derivation of Our Lady of Mount Carmel, who is Mary.
Various shortenings and derivations also alter your name - Jose is Joseph, Marianne is still Mary, Liza is Elizabeth. If your name simply cannot be traced back to a saint, you may celebrate on All Saints' Day.
While children get big parties for both, one or the other tends to fade into the background for adults. It's generally considered tacky to throw a big party for both your birthday and your name day if the two fall close together. Of course, those named after the saint on whose feast day they were born are out of luck as far as the double birthday goes.
The party lacks the cake and candles of the birthday party, but gifts are welcome - but be aware of cultural customs first. In Greece, cash is considered inappropriate, while in Hungary, men expect a bottle of alcohol and women expect flowers. Take your cue from the culture whose calendar you're using.
Otherwise, a name day party can be a festive occasion with food, dancing, and drinking, or a smaller family affair if the honoree desires. Celebrations may be called off entirely during mourning or other solemn occasions.
Of course, being a religious day, you should really think about attending mass if your name is associated with a major saint. The major saints, like the Virgin and the Apostles, traditionally inspire a mass. Lesser saints are accorded rankings based on importance, and services become simpler and scaled-down as importance decreases.
Lesser saints' services are generally not obligatory, but a small gesture would still be appropriate for the one celebrating. Even if it's just a small prayer, it's a mark of respect to the man or woman whose name you carry.
The custom of celebrating name days has never been as popular in the U.S. as it is in other countries, and it's receding in importance even in places where it was once a bigger celebration than your birthday.
Why not bring this lovely tradition back - we could all use another reason to celebrate, and doing it in honor of both a loved one and a person who dedicated (or gave) their life to God is a noble excuse.