Set the form's KeyPreview to True then add code similar to this.
Code:
Private Sub Form_KeyUp(KeyCode As Integer, Shift As Integer)
    Static bShow As Boolean
    
    If KeyCode = vbKeyE Then
        If Shift = 1 Then
            bShow = Not bShow
            cntlX.Visible = bShow
        End If
    End If
End Sub
Change cntlX to your control name
It will toggle when you hit Shift + E, you can change the key to whatever you like.

P.S. this could be called an Easter Egg