I have a seagate 320 gb external hard drive(with usb) Currently i am using a hackintosh and i will switch to Mac in a month. In my external HDD i have 200gb of pictures-movies-tv shows-documents. It is formatted with NTFS so i use it with Macfuse and NTFS 3G. when i get a macbook pro 15" i5 with 320gb hdd i will transfer all 200gb to my MBP, format the HDD to Mac os journaled instead of ntfs and use the hard drive for time machine. After that i will still have some space. I want to use that space for carrying around documents for example to carry my presentation with me to the school. Can i use it like that? Also computers at school uses Windows, can windows read and write Mac OS Journaled format? Thanks. additional quick question: In windows if HDD is full pc gets slower, do macs get slower when hard drive is near full?