Here's something I can't figure out.
If I run this by double-clicking in an empty cell, it enters the
username then stays in edit mode with the cursor flashing in the cell.
When I duoble click on a cell that has something in it, the program
does what it is supposed to do and skips down to an empty cell and
enters the username and "finishes", the cursor not flashing. I would
like to have them both "finish". How is that controlled?

Private Sub Worksheet_BeforeDoubleClick(ByVal Target As Range, Cancel
As Boolean)
If Target.Column = 3 Then
Do
If Selection.Value < "" Then
Selection.Offset(1, 0).Select
End If
Loop Until Selection.Value = ""
Selection.Value = Environ("username")
End If
End Sub