I've got an external HDD, and the data on it I don't need. Am going to reformat it to transfer everything on my Mac over so I can update to Mountain Lion, but am unsure what to format it as. I realise NTFS isn't suitable for OS X, and Mac OS Extended won't be any good for a Windows machine - so will I be able to format as FAT32 and then use on both Windows and OS X? I want to be able to use it on both systems.