I have an issue where I'm trying to remove duplicate rows from a table
(leaving one so that it is unique) and then another issue where I'm
trying to remove all duplicate rows in a table such that there are no
rows containing that data left.

The spread sheet consists of rows like this:

Col 1 Col 2 Col 3 Col 4
Stuff Stuff Something 1
Stuff Stuff Something 1
Stuff Stuff Stuff 0
Stuff Stuff Nada 1
Stuff Stuff Nada 1
Stuff Stuff Nada 1
Stuff Stuff Stuff 0
Stuff Stuff Stew 0

In this case Column 3 is the one that needs testing to see if they are
dups, all other columns are irrelavent. Basically what I was thinking
was, in terms of an algorithm:

Mark all duplicates with 1 whether they are above or below (thus
needing the OR statement):
=(if below == above, 1 OR if above == below, 1) Then delete all rows
with 1 in that Column 4.

The standard if that marks all but last duplicate could be:
"=if(A2=A1, 1, 0)" After this things really start getting fuzzy as
I'm not familiar enough with programmatically working with Excel.

I'm at a loss as to how to do this in Excel or if there would be an
even better way of doing this. I would appreciate it much if anyone
can demonstrate how this would be accomplished.