Last year, one of our favorite laptop backpacks (and really, it still is) was the Booq Boa Squeeze. More of a padded gear tube with arm straps and plenty of pockets, it managed to be stylish, compact, sturdy, and roomy all at once.
For something a little bigger--no, make that a lot bigger--Booq's sizable Boa Flow might be what you're looking for. OK, honestly, the bag's gigantic. A large reinforced black-and-orange curved shell-shape lined with some useful pockets and plenty of interior room, the Flow will resemble nothing so much as a giant Koopa shell or neon Teenage Mutant Ninja Turtle costume. It's not light, either: at 4.5 pounds for the medium-size Flow and 4.9 pounds for the XL-size, this bag's heavy even when empty. It also isn't cheap: $199 might be too steep for many bag-buyers. It's twice the price of the Boa Squeeze.
To its credit, however, it keeps its shape and stays strong. A large interior, nearly enough space to be called a weekend suitcase, can hold clothes, small packages, and whatever else you can think of. Laptops actually slide into a separate rear-zippered compartment, which has very thick and rigid padding. Even semithick 17-inch desktop replacements can fit here, no problem, providing you've bought the XL (which, incidentally, happens to be same price as the M).
The ergonomic back padding is generous to say the least: three big orange slabs of foam provide ventilation, and the curved arm straps are comfortable, though lack smartphone pockets like the Squeeze had. There is a padded sleeve below the thick, padded top handle to the Flow where an iPhone, MP3 player, or other smartphone can be tucked in, but its placement while wearing the Flow could leave your treasured gadget vulnerable to being stolen.