Don’t be fooled: Numbers isn't just a spreadsheet program. It’s also a great list-making app, among other things, especially on the iPad. For instance, before traveling, I use Numbers' Travel Planner template to combine my travel itinerary, packing list, airline and hotel reward program account numbers, and activity list into one multi-tabbed spreadsheet, which syncs to my iPhone, too. The app also has templates for a mortgage calculator, loan comparison, expense reports, budgets, personal savings and more. You can import and export to Excel, of course. But after using Numbers for a while, you may not want to.
Check out InfoWorld's rundown of the right office apps for the iPad