I'm not going to trust my precious Excel pivot tables to a web app given how crappy the current generation of browsers is (I've lost count of how many times Firefox crashed on me) but this is impressive:

For people who don't see the value in pivot tables, I'll say this: do you really know where your revenue is coming from? We've met our revenue plan for the first four months of the year with uncanny precision (just a couple of grands above it) because we know how to split and dice our sales data in many, many ways. I don't know how you can be a business leader and not be a spreadsheet jedi. Not that everything happens in the spreadsheet of course, and without people skills you have nothing. But you need to be able to make the numbers tell you all their little but important stories. They show you the hidden weaknesses, point to potential for greatness.