It is nice to find out what weekday you self or some one else was born.
This App does this and more.

The Gregorian calendar is internationally the most widely used civil calendar It is named after Pope Gregory XIII, who introduced it in October 1582. The calender was adopted by the countries from 1582 (Venice) to 1918 (Russia)

The Weakday app displays the weak day of a given date and even display the year in roman digits.