In short:
If you need to share disk on Mac and Windows use FAT32 or NTFS. FAT32 limitation is that per file can have only 4GB. No way overcoming that. NTFS trick is that you need to have another software installed as well as explained above.
If you don't have the need to have the disk being shared on Windows then native mac all the way I guess
For more info here:
http://en.wikipedia.org/wiki/Comparison_of_file_systems

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Added on April 25, 2010, 4:10 am

Can. In short anyone studying or working in education sector is eligible. You would fall under K-12 category

from what i understand,
if u want no 3rd party crap, then fat32 is the way to go for mac to mac transfer...
meaning, format the drive to fat32 format not NTFS...
the good thing is that fat32 can be read on mac as well as pc...so u wun hv compatibility issues...
the bad thing is that u can transfer files bigger than 4gb on fat32...
the option u hv if u transfer large files alot is using a NTFS format provided u use ntfs-3g on mac.. that solves the little bit of prob...