I'm looking for some advice. The SSD constraints (256MB) are forcing me to consider external storage and back-up strategies. Note: 512MB option would have only delayed this discussion. Here's what I've got: (1) RMBP with 256MB, 16GB (2) 1 TB USB 3.0 external - Client data files for work (3) 1 TB USB 3.0 external - Time machine back-ups My concern is primarily related to my Work stuff. I drag ACTIVE client files from (2) to the RMBP to work on them, and then send them back occasionally to (2) for storage. Time machine will catch these files, but only while they reside on the RMBP. I worry that disk (2) could fail w/mission critical files, so I also need a backup for (2). Back-up for the Time Machine drive (3) is not so critical as the RMBP itself is essentially my fail safe. I use Carbonite on my current PC Laptop, provided by my company. Seems to work well enough, but is a real resource hog - and will not be installed on my RMBP. I presume Crash Plan is something similar to Carbonite. Can I add the external drives to the mix?? Any suggestions to address my requirement??