Aiming to have a large internal HDD to store files, and several OSes on separate disks. They all need to read and write to one storage drive. Ubuntu (13.04+) Mac OSX (10.8+) Windows (7+) What format should the drive be? Would like to avoid buying third party software, here's what I have discerned so far: NTFS - Can't be written to by Mac without buying third party software? ext3 - Windows can't read, third party software in development. Mac has OSXFUSE HFS+ - Buy third party and/or faff around to get working on windows exFAT - Cross platform, but breaks MS patents?