Data Validation List based on another data validation list

Have you ever thought how simple life could be if you could make your spreadsheets act more like a form without going through the trouble of creating one?  In today's example you can create a list of values in one field where another list is populated based on what the user selects!

Sub list2()

    With Cells(1, 2).Validation

            .Delete

        If Cells(1, 1) = "one" Then

            .Add Type:=xlValidateList, Formula1:="A, B, C"

            ElseIf Cells(1, 1) = "two" Then

                .Add Type:=xlValidateList, Formula1:="D, E, F"

            ElseIf Cells(1, 1) = "three" Then

                .Add Type:=xlValidateList, Formula1:="G, H, I"

        End If

    End With

End Sub

The above example will only refresh when the macro is run.  If you want this to run as soon as a value is chosen you may want to set this into the worksheet where an event will trigger it to run.