What I want to do is to have a cell 'remember' a barcode that has been used
to indicate that a book has been taken out and then returned. For e.g.,

Barcode Date-Out Requested by Date-In

801010101 07/08/08 J_doe@cc[1]. xxxxxx

The 1st time the barcode is scanned for the item the date will auto populate cell 2. When it is returned, I want to be able to scan the barcode and have the 'memory' of that 1st scan auto populate the Date-in cell (cell 4) all in the same record.