Ok, so I have Custom PC and an iBook G4, both of which I would love to use with my new Western Digital "My Book" External HD(500GB)... I understand that on the windows side of things I can't write a file any larger than ~4GBs(For FAT32) to the drive, but my Mac doesn't have an intel so I'm hesitant to try adjusting my mac to read and write to NTFS. Does FAT32 prevent my mac from reading or writing 4GB+ size files?? I plan on doing a lot of video editing, I can handle it of I can't write 4GB+ with my PC, but that could prove an issue if I can't write 4GB+ on my mac also. What Format is best for me to use. I primarily use my MAC, but I do some active screen captures on my PC that I would transfer to the External for working on with my MAC. I'll ask/say more after I get a few responses. If you do respond and are fairly knowledgeable on this subject, please check in every once in a while until I've resolved my issue?? Thanks a lot.