It's not too difficult. I usually put a formula in an unused cell that
points to the cell with the link (like =B3) so that the change in the link
initiates a worksheet recalc. I use a sheet event to act on the recalc.
Right click the sheet tab, choose View Code. At the top of the code module
that pops up in the VBE, select Worksheet from the left hand dropdown, and
Calculate from the right hand dropdown. This code outline appears in the
code window:

Private Sub Worksheet_Calculate()

End Sub

Let's say you're taking the value in cell B3, and storing it in column F,
and the time in column E. This is the code you would use:

Private Sub Worksheet_Calculate()
 Dim iRow as Long

 iRow = Me.Range("F65536").End(xlUp).Row
 Me.Range("E1:F1").Offset(iRow).Value = Array(Now, Me.Range("B3").Value
End Sub

Of course, a little validation and error proofing would help as well.

- Jon
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Jon Peltier, Microsoft Excel MVP
Tutorials and Custom Solutions
Peltier Technical Services, Inc. - http://PeltierTech.com
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