If you want to protect your algorithms (silly, since I guarantee they aren't a unique or as secret as you think, but that's a different argument) then putting them in a protected excel file is ...

If you have sensitive data you'd like to keep from prying eyes in a Microsoft Excel file, the easiest way to protect it is with Excel's built-in password tools.

The 2007 versions of Word, Excel, PowerPoint, and Publisher list an option to remove personal information from file properties on save (this may be grayed out), as well as a Document Inspector ...