This won't work... functions cannot "access" anything outside of its
own cell? So, I need a sheet event to run this.

After a cell value changes anywhere on the sheet, or something, I want
to recognize 'calculations complete' and then run a column hiding sub
(). Or, I think that's what I want. I need to hide columns based on
data and it appears a user function won't do it. Suggestions? Thank
you in advance.


NO GO below (doesn't hide itself) (maybe a bug?)

Function columnVisibility(hide_if_lt_zero As Long)

Dim myRng As Range
Set myRng = Application.ThisCell

If hide_if_lt_zero < 0 Then
myRng.EntireColumn.Hidden = True
Else
myRng.EntireColumn.Hidden = False
End If

columnVisibility = 0#

End Function