GS explained on 9/2/2011 :
Try...

Sub DenoteCellsGreaterTanZero()
Dim r
For r = 1 To ActiveSheet.UsedRange.Rows.Count
If Application.WorksheetFunction.CountIf(Rows(r), "0") 0 _
Then Cells(r, 1) = "x"
Next 'r
End Sub

Note that this is a programming group!
BUT
Since you asked for a formula...

=IF(COUNTIF(B1:AE1,"0"),"x","")

--
Garry

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