I currently have a MacBook Pro (500 GB SSD + 1 TB HDD ) and a MacBook Air (128 GB) for college. At first I thought I will be using my MBA only on the go and my MBP at home, but it turns out I'm using the MacBook Air for 95% of stuff and my MBP ist completely unused except when needing media data (music, photos and movies or files). I also wanted to replace the MBP with an iMac, but I wouldn't be using it much. I'm now planing on selling my MacBook Pro, but the big question now is where to store my personal data files (about 300 to 400 GB). I'm thinking about it for a week now and I couldn't make up my mind. PLEASE NOTE: I would encrypt anything using FileVault 2 no matter which option I choose (however using a NAS would make it impossible except using a .dmg image file). Solutions I've come up with: - sell MBA 128 GB and buy 256 GB/512 GB -> basically the easiest thing, but very expensive. I would worry more about carrying my MBA as mine is worth € 800 and the 512 GB would be worth at least € 1600, but I would have all my data in one place and I couldn't "lose" without losing my MBA itself. - use a special SD card for the MBA -> for about € 200 I would have 256 GB of extra storage (~80 MB/sec. read/write) in my MBA. I could have my files anywhere, but I might get short on storage and it blocks my SD card slot and I'd have to use a USB adapter for my camera's SD card. Moreover, it is easier to "steal" my personal data as someone only has to remove the SD card. I encrypt however, so data should be safe. - use an external hard drive or SSD -> this would be about € 250 and I could have almost full SSD speeds with an external SSD housing. I could easily expand the storage, my data could be easily separated from the MBA itself, so if someone steals it on the go and my external SSD is at home, my data is completely safe. I would only attach it if I needs to access files and I could easily remove it again. Only the usage on the go would be awful as using an MBA on your lap with an external drive is uncomfortable and quickly storing it needs one extra step: disconnecting the external drive. - use a NAS -> this would give me several benefits, but the iPhoto library can't be stored there and even though I could move my "original" iTunes library with all songs there, once on the move I'd have to switch libraries to use the one stored on the MBA itself. I would only benefit from it for several firmware files, normal data and maybe my videos. As I won't be using an Ethernet adapter for the MBA, speeds wouldn't exceed 15 MB/sec. which is bad for transferring or copying files. Maybe you could a 5th solution or do you suggest a combination of multiple solutions above? Then please tell me! So I need to put my iPhoto library somewhere, store firmware files, installer files and anything else and to be able to store my iTunes Music folder somewhere. I'm using iTunes Match, but I need to have them locally (iTunes Match is not really a backup service and if the subscription couldn't be renewed, I'm losing all my music). I would need to have a library to store all songs and to be able to just download certain songs on the go. I don't know how you could easily do that (except using the SD card solution and to keep the SD card plugged in). Files: ~30 GB iTunes ~150 GB videos ~40 GB iPhoto ~30 GB backups of Android, iPad and firmwares -> will increase over time of course! I hope you can help me out. If you read this post that far, you are one of the few. Please help me make up my mind!