I have just gotten a Macbook Air 13" ultimate...and am trying to get everything on my network set up. I would like to use Time Machine to backup the mac, but I also need to be able to back up at least one windows machine (and maybe two). AND I would like to be able to use that same drive for extra storage. My router does have a USB port so I think I'm good there. I already have a 1 terabyte back up drive (Seagate) but it came with proprietary software and I have not found a way to make it fully accessible to all computers. It works with Windows XP but there is no software/drivers for Windows 7. It simply isn't supported anymore. With that said, I would like to avoid any type of drive that requires proprietary software just to perform a back up. I would far prefer a drive that allows me to install the backup software of my choice on the computer of my choice to back up to the drive. I am not sure what I should be looking for or if it needs to be partitioned. I'm honestly just not even sure where to start. My thought is that I would like to be able to save all my pictures and other large files to this drive as extra storage space that my Macbook Air can access as an additional "D" drive. I would also like to be able to do Time Machine backups to this drive. And I would also like to be able to do Windows backups to this drive. And I would like all computers to be able to access this drive as a "D" (like a "C" drive). What would you all recommend? I think 1 terabyte would be sufficient for my needs.