Add another column to count the number of occurences a particular name
shows up. Assuming the name field is in column A, use this formula in
row 2 of the new column then copy down the length of the sheet.
=IF(SUMPRODUCT(--($A$1:$A$6=A1))<3,"Delete","Keep")

Sort the table by the new column and all of the Delete's will be
bunched together.

- John Michl
www.JohnMichl.com