Go to

Page Setup then Header/Footer

Whoops didn't read far enough ahead... unless you do some kind of Workbook
activate event or something like that... I have no clue.

I won't speak for Word but in Excel you can change the default Template for New
workbooks to print the date on all sheets when printing.

Note the "New workbooks"

Existing workbooks would need to be set up via manual addition to the
header/footer or via VBA macro.

To change the default Template for all New workbooks...................

Open a new workbook.  Customize as you wish.
Note: you can set all sheet footers at the same time by "grouping" the sheets.
Right-click on a sheet tab and "select all sheets".  Set up a footer on the
active sheet and will be done to all.  Ungroup when setup is complete.

File>Save As Type:  scroll down to Excel Template(*.XLT) and select.  Name your
workbook "BOOK"(no quotes). Excel will add the .XLT to save as BOOK.XLT.

Store this workbook in the XLSTART folder usually located at........

C:\Documents and Settings\username\Application Data\Microsoft\Excel\XLSTART

This will be the default workbook for File>New or the Toolbar button File>New

Do not use File>New...Blank Workbook or you will get the Excel default workbook.

Existing workbooks are not affected by these settings and would require a macro
or grouping the sheets and make settings as above.

You can also open a new workbook and delete all but one sheet.  Customize as
you wish then save this as SHEET.XLT in XLSTART folder also.  It now becomes
the default Insert>Sheet.

More can be found on this in Help under "templates"(no quotes).

Gord Dibben   Excel MVP