Mac,
If I understand your question correctly, then what you want to do
cannot be done simply with formulas. One basic reason is that the
CONCATENATE() function in Excel does not work similar to aggregate
functions like SUM(). Once I tried to solve this problem using Circular
References and Iteration mode, but it was for the concept only. Any
such solution would probably provide you with more complexity than you
currently want to avoid.

Kostis Vezerides