=IF(COUNTIF($D$1:D1,D1)=1,D1,"") - Entered into E1, E2, etc.

... and perhaps simpler to illustrate (going back to your orig. post)

Put instead in E1:
=IF(D1="","",IF(COUNTIF($D$1:D1,D1)1,"",ROW()))

Put in F1:
=IF(ISERROR(SMALL(E:E,ROW())),"",
INDEX(D:D,MATCH(SMALL(E:E,ROW()),E:E,0)))

Select E1:F1, copy down to say, F1000
to cover the max expected extent of data in col D

Col F will auto-return the uniques list from col D, all neatly bunched at
the top

Here's a quick sample to illustrate the above construct:
http://cjoint.com/?cniYDLtDb8
PaulQuincy_wks_1.xls
--
Max
Singapore
http://savefile.com/projects/236895
xdemechanik
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