I need more options for a spreadsheet than I see in the spreadsheet plugin-- for instance, excel-like tabbed worksheets and conditional formatting. Is there any way this would be available, or am I out of luck?

I want to use an excel spreadsheet (or something like it) in pbwiki-- it needs to be editable in the wiki, have multiple tabbed worksheets in one workbook, and have conditional formatting. As far as I can see, the spreadsheet plug in doesn't have those features. Suggestions? Thanks!