tmp := ExtractFileName(L.Strings[i]);
tmp := Copy(tmp, 1, Pos('.', tmp) - 1);
NewName := Format('%s%s.%s', [ExtractFilePath(L.Strings[i]),
                                 tmp,
                                 FormatDateTime('ddmmyy_hhnn', Now)]);

tmp := Copy(tmp, 1, Pos('.', tmp) - 1);
NewName := Format('%sNew_%s', [ExtractFilePath(L.Strings[i]),
                                  ExtractFileName(L.Strings[i])]);

NewName := ChangeFileExt(L[i], FormatDateTime('ddmmyy_hhnn', Now) + ExtractFileExt(L[i]));