"Do we forget to pray for souls in Purgatory? Perhaps a handy reminder such as the one found in the friary of San Giovanni Rotondo, often made use of by Padre Pio, should have a place in our homes. Located on a landing in the cloister is a list of one hundred sins, many of which souls in purgation suffer to be cleansed of, titled 'A Short and Easy Way to Pray for Souls in Purgatory'. Below this is a box containing numbered disks corresponding to the list of sins. Padre Pio would, when passing by, select a disk and recite an 'Eternal Rest' for those souls being purged of the indicated sin. Then, much happier, he would proceed on his painful way."
~ Fr. Alessio Parente O.F.M. Cap., from The Holy Souls ~