Additional
Information: The Microsoft Excel spreadsheet application stores spreadsheets in a OLE2 compound file based format. The name of the files typically ends with .xls or .xlb.
OpenOffice.org's Documentation of the Microsoft Excel File Format OpenOffice.org's Documentation of the Microsoft Excel File Format: Contains a description of the binary file format of Microsoft Excel, including all available Excel versions (for Windows) from Excel 2.1 to the current Excel XP. [PDF] (Microsoft Excel) http://sc.openoffice.org/excelfileformat.pdf