Within a cell on a spreadsheet I want to record the last saved (or modified)
date of another (non Excel) file.

Example - I have a Powerpoint presentation that was last saved on 01/09/03.
I want cell A1 of an Excel file to display "01/09/03" and update when the
Powerpoint file is subsequently saved. Is this possible?

The excel file will be opened regularly, so some form of Auto_Open macro or
VBA code that updates cell A1 will be perfect.

Thanks in advance for any help!