Hi Codequest...
You can do this in two simple steps...
1...Select your range as in A Column assuming you have string ids there..and sort it either ascending or descending order...
2...Go to Data-->Subtotal-->Then it will give following options-->
a...At each change at string Id...
b...Use function....-->Sum...
c...Add subtotal to values...
and Hit ok...and you would be good to go...
Second way to do the same is by pivot table...
1...Select your data....
2...Go to data-->pivot and wizard..Hit Next...In which data to use...you would have already your data selected...Hit next...Then click layout and in row drag your string id there...and in data drag your value there and choose condition sum...hit Ok...and then click finish....and you would see a new sheet with pivot showing sum of the values in it...
Saurabh...