Something like this would work:
[Code="Other"]
WITH MEMBER [C]
AS
SUM(NULL:Axis(1).Item(0).Item(Axis(1).Item(0).Count-1).Hierarchy.CurrentMember, [Measures].[Your Measure])
SELECT
{[Measures].[Your Measure], [c]} ON 0,
[Your Dimension].[Your Hierarchy or Attribute] ON 1
FROM
[Your Cube]
[/code]
Hope that helps 🙂