[Endoperez]

I haven't needed to use many .xls files yet, and I think OpenOffice can handle them anyway. The only time I regretted not having MS Excel was when I found out that pretender cost-counting Excel file. It used many macros, but seemed to be able to quickly compare different pretender/nation/scale/theme setups. I found it from SunrayBe's site, IIRC.