What exactly are you looking for? A hard case or a soft one?
For me, a guy at work had one of those Wenger/Swiss Army laptop bags and I got one for about $50 or $60 because I saw just how awesome it was.
It has a main pocket for a ~15 or 16-inch laptop, which is fully padded. The laptop slides into the pocket, which is secured at the top by a single velcro strap. In front of the pocket is a gap where you can put flat stuff, and within the same compartment, facing the laptop, are two mesh pockets which are wide enough for the chunkiest of external HDDs.
There's another zippered compartment in front of the laptop area which contains several smaller pockets large enough for at least two slim external HDDs. Mounted in front of those pockets are smaller pockets, plus there's the general gap left over within that compartment. And in front of THAT area is the very front of the bag which is a huge pocket zippered at the top. And at the very back is, you guessed it, yet another compartment containing a flat divider for easy access to important files, plus another, larger, flat area.
The back of the bag has a small, velcroed gap in the webbing where you can slip it over a carry-on handle. The bag has a main strap plus the standard dual-grip handle present on most computer bags.
Overall this is one of my favorite purchases over the past five years. It's large enough to carry the fat PS3 or the PS4, along with several games, two controllers, etc. I normally use it to carry my MacBook, including a shitload of AV and PC cables (VGA, HDMI, DVI, analog audio, travel mouse, USB bits and pieces, etc. This [http://www.amazon.com/Wenger-Swiss-64038010-Carrying-Notebook/dp/B00V2S23XG/ref=sr_1_16?ie=UTF8&qid=1441623302&sr=8-16&keywords=wenger+laptop+bag] bag looks very similar to what I have.
And if you wanted to go the ultra paranoid route, there's always off-brand watertight cases [http://www.amazon.com/Seahorse-SE520-Protective-Case-Black/dp/B000OVN3HM/ref=sr_1_fkmr0_2?ie=UTF8&qid=1441623578&sr=8-2-fkmr0&keywords=bolton+watertight+case] with pluck-to-size foam cube inserts which you can break apart to make a custom fit. I have one similar to this for ammunition storage.
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Now, if you wanted to get a little hardcore, I would recommend a bag from Courierware [http://courierbags.com/]. I have two of their bags. I think they still offer a lifetime warranty on stitching, plus all their bags are constructed of a two-ply material which, once combined, form a waterproof seal. I know this to be true because someone accidentally spilled a beer in one of my bags (long story) and it held it like a bucket.
The outside material is a super tough, heavy duty cordura nylon that feels almost rough to the touch. My first bag was used to travel around the country, and it was overstuffed the entire time. Their bags will last a very, very long time. If you can spare around $140, I cannot recommend Courierware enough. They also offer accessories like inserts but first and foremost I would recommend their optional shoulder pad [http://courierbags.com/collections/accessories/products/shoulder-pad], which can be used on any bag with a shoulder strap. I bought two extras and used one for my Wenger.
