The trouble with having an nMP is that you soon realise just how noisy everything else is and these noises and vibrations completely spoil the computing nirvana. I don't mind the whir of a mechanical drive, but I detest the vibration and the fan noise. I have stuck vibration isolation pads onto every storage device and it helps quite a lot, but I still find the noise of fans from my various thunderbolt multi-bay enclosures very distracting, so I only power them on when necessary. The one drive that I keep constantly connected is a 2.5" 2TB WD external drive, which contains my iTunes library. Unfortunately the iTunes library is now 1.8 TB and it will continue to grow, so I am forced to look for larger options. Seagate offers a 4 TB 2.5" and so does WD. They are just 2 x 2 TB drives and the reviews indicate that the WD 4 TB with thunderbolt is very noisy. I haven't found much info regarding the Seagate though. Alternatively I could look at 3.5" drives, but it's an extra hassle to get power to them neatly and it is not always clear which are passively cooled from the spec sheets. I know that the latest Lacie thunderbolt drive is passively cooled and is meant to be quiet, but I am curious if anyone has other recommendations?