No, in general, formulas can only return values to their calling cells.
However, you can use an event macro that will check your cell each time
the sheet is calculated, say, and run the macro if the value of the cell
is 1. Put this in your worksheet code module (right-click the worksheet
tab and choose View Code):
Private Sub Worksheet_Calculate()
If Range("A1").Value = 1 Then MyMacro
End Sub