What else can you do to a spreadsheet to make it more useful? For some people, those who have huge amounts of data to deal with, the maximum size of a spreadsheet can be a limitation. Excel 2007 can now handle worksheets with over 1,000,000 rows and over 16,000 columns, which should be enough for just about anybody (that's not a challenge). It should give you confidence to expand your working area to the size you need to work comfortably.
Perhaps more directly useful is the new support for dual and multi-core processors. With more and more machines being built around Duo and Quad chips, being able to take advantage of their multithreading should ensure calculations in big worksheets complete quicker than in earlier versions.
Sorting data, so that you can view items according to multiple criteria, has a lot more depth, with up to 64 levels of condition. You can also create tables from your data, giving them preset styles and automatic drop-down menus, which can be used to quickly change the sorting and filtering. If you need to fiddle around with live data under multiple headings, these quick formatting and distribution facilities can improve productivity considerably.
You can also save worksheets in PDF format, useful for sharing information, while restricting the changes that can be made to it. PDF support doesn't come as standard with Excel 2007, but is available as a free download from Microsoft. The quickest way to get at this is to search help for ‘save worksheet as PDF' and follow the link. Once downloaded and installed, the PDF option is added to the Office button, Save option and can be used just like any other file format. Any page format settings made for printing the worksheet are honoured when you create a PDF.
Excel 2007 has come a long way since the 2003 version and includes a number of improvements to the way you use it. Setting up charts and pivot tables relies far less on Wizards, which take you out of the program proper, and instead stays within its Ribbon and dialogs but does more for you, so the default settings are often all you need.
Run through the videos which accompany this feature and you'll get more of a feeling for the way Excel 2007 can be used as a freeform tool for many purposes, rather than just as a number-cruncher for financiers and scientists.