[lmikle]

А вот так слабо:

Код:

function DayOfWeekStr(ADate : TDateTime) : String;
begin
  Case DayOfWeek(ADate) Of
     1: Result:='вс';
     2: Result:='пн';
     3: Result:='вт';
     4: Result:='ср';
     5: Result:='чт';
     6: Result:='пт';
     Else Result:='сб';
  End;
end;

...

Label1.Caption := DayOfWeekStr(Date);
Label2.Caption := DayOfWeekStr(Date+1);