I just got upgraded to Windows 7 from Windows XP Professional. In the past, I had a .xlsb file located in C:\Program Files\Microsoft Office\Office 14\XLSTART. Each time I started Excel, this file would load as hidden and I had macros I was able to link to icons in my customized quick access toolbar.
Now that I have upgraded, I wish to be able to do the same. I used the ? Application.StartUpPath in VBA Immediate Window to determine the new path which told me: C:\users\*username*\AppData\Roaming\Microsoft\Excel\XLSTART\.