Is there anything you can't do with Excel?
We have a project manager in our company who was responsible for site rollouts of desks, network points, phones etc etc for nearly a thousand users. He found that the as-built drawings supplied by the contractors were less than adequate so he made his own - in Excel. They were so good they looked like CAD plans, but the maniac had 'drawn' them in Excel!
No, I wouldn't have believed it either, but I saw them with my own eyes both on paper and right there in Excel on the screen
What other esoteric uses are there?