Rabbi Meir Shalom of Porisov would make it a point to distribute money to the poor on the day after Purim.  He would say “Since there is a special obligation to give gifts to the poor on Purim, people neglect this commandment the day after Purim.  It is especially important to perform a neglected mitzvah. ~ Derech Tzadikim as quoted by R’ Zelig Pliskin