Nice job, Sunil. I especially liked the fact that you compared what some folks go through with multiple queries (in one form or another) and the simplicity of WITH ROLLUP.
As a side bar, you shouldn't use ORDER BY with either ROLLUP or CUBE... it's one of the very few places in SQL Server where the order is pretty much guaranteed to be correct and in the order expected.
--Jeff Moden
Change is inevitable... Change for the better is not.