In a listview of all Calls, the "Related To" column is not sort-able like all the other columns. When a call is logged we relate the call to the Account which does show in the listview. However in order to see all the calls sorted in alphabetical order by the "related to" column you would need to "sort" it and there is no icon to sort the "Related To" column.
Maybe it isn't possible? What am I missing?