Bought this bag to carry my school books and supplies, as well as my laptop 15.6". It holds everything I need it to with room to spare. The shoulder strap makes it easy to carry even when I have it loaded down.
When I first got this bag I thought it was maybe too big. I got the large size, and it is kind of big but it is also very adjustable. This bag is so well designed that it can be a commuter bag, an overnight bag, a weekend trip bag, a flight bag... I have used it as all of these things in the six months or so that I have owned it. It also keeps me organized with enough different pockets that everything can have its own 'place'. The separate computer compartment is really roomy and doesn't interfere with the bag's capacity. The tablet sleeve is a bonus. There is a compartment on the bottom of the bag for power bricks, which has an additional benefit of making the bag balance easily even when it is full. The final feature I want to mention is the zippered side pocket for a wallet. I didn't see why this was even mentioned in the product description, but it turns out to be one of my fave features. It turns out that not having to adjust the strap on the bag, or lift up the front flap to get at your wallet makes life a bit less exacerbating in ways I didn't expect. This is for sure one of my favorite things that I have ever owned. I want Timbuk2 to design my house.