When data changes in a column push data to another cell

[BrewerChris]

I'm trying to track volumes of beer through a tank.  I have a column set up for "Name of Beer".  At the top of the sheet I have a cell that lists the current beer in the tank.  What I'm looking for is a formula that changes the current name only when the name changes in the Name of Beer column.  For instance. cell A2 lists current beer, lets say "Alpha".  Then through a few days I package off the balance of "Alpha", then put "Beta" into this tank.  When I change the "Alpha" in lets say C3 to "Beta", I want the name in A2 to reflect the new name.  I don't even know if this is possible.

[#2]

simply you could use in A2 the formula =C3 but I think you probably want something more/different than that.

[#3]

Yes as I go down row after row, I want A2 to reflect the latest C3,4,5,6 etc. What I'm thinking is an "if then" statement but I can't figure out how to make it work.  Is there a way to push data to a cell rather than pull data from a cell?

@mtarler 

[#4]

oh. maybe something like:
=INDEX(C:C, COUNTA(C:C) )
this will show the last value in column C assuming there are no blanks. If there are/need to be blanks (of an unknown amount because if you know there will be exactly X number blanks at the top you can just subtract that amount) a different formula would be needed.
And the only way to 'push' data would be to use a macro. Cell Formulas only display the result of the formula in that cell.