| Probably the best solution would be a whole-disk encryption (perhaps something like the Seagate(?) solution they're coming out with in a few months).  That or a third partition, FAT32 or something, that you can find a piece of software that will create an encrypted file and is cross platform.
 I don't think you'll be able to find anything that will let you read encrypted HFS partitions on Windows and encrypted NTFS partitions on Mac, though.
 
				__________________Eat antimatter, Posleen-boy!
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