So WD Passport comes in a format that is compatible with Windows and Mac. However, that has a 4 gigs file size limit and is not enough for some of my .iso files. So, can a genius here please tell me what that format is called that it ships with. I heard windows uses NTFS (maybe I have the letters wrong). I looked in to this 3G thing by google but I can't figure it out. http://en.wikipedia.org/wiki/NTFS_3G Does anyone have a blog with step-by-step instructions on how to make it work? (I am not capable of compiling stuff [i think that is the word] which is where I always ran in to trouble in the past). Can I reformat the WD Passport 320 gig to NFTS format? Will things like Imovie and final cut studio (if I ever get it) know how to utilize this NTFS-3G thing to write on to the external directly? What is the Mac format called that has no file limit size? What would you recommend I do? I own PC desktop with 3 externals hooked to it. Can be networked to my mac to transfer files but it's so slow compared to usb 2.0 directly connected. I have a macbook pro with practically filled native HD and one wd passport but with the 4 gig file limit. I really could use some help - such a noob with mac problems.