Triangle 1992-6. Continued from Superman: The Man of Steel #8 and continues in Adventures of Superman (1987) #487.
The Man of Steel makes his annual trip to the local post office in order to read the thousands of letters sent general delivery to "Superman." Most letters are only greedy schemes to Superman to help the writer get rich, but many are heart-breaking tragedies asking for help in last-ditch desperation. Superman manages to help unite a family torn apart by the horrors of war, has to explain to a young fan why even he couldn't save his father from heart disease, and helps bring some joy to some local orphans.