Tommorow is All Souls Day in the Catholic Church. All Souls Day is part of the Tridiuum of Halloween, All Saints Day, and All Souls Day, which is why parts of modern Halloween actually came from the Catholic Church. I know that all Saints Day in the Eastern Orthodox Church is on the Sunday after Pentecost. Do we have something like All Souls Day in the Orthodox Church?
In a way all Saturdays are days for remembrance of the departed, and there are several "Soul Saturdays" set a side for more specific commemoration of the departed:
The Saturday before Meatfare
The 2nd, 3rd, and 4th Saturday of Great Lent
The Saturday before Pentocost
*Specific to the Russian tradition, usually Saturday before St Demetrius day