Timbuk2, maker of some of my favorite laptop bags, recently sent us a brand-new one to try out: the Hacker. It's one of the more versatile bags I've come across; it can be carried like a messenger bag by using an included attachable strap, or turned into a backpack via concealed straps; there's also a handy grab handle.

For my commute, I've been using the Hacker in its backpack incarnation. I can attest that it's quite comfortable to carry, even when loaded down with a laptop (it'll accommodate a laptop up to 15.4 inches) and 24 cans of cat food. Timbuk2 makes bag straps that are adjustable on the fly, so you can get the right degree of snugness easily. Inside are plenty of pockets and pouches for gadgets, pens, and so on; the bag also has a couple zipped outside slots handy for IDs and train passes. And the laptop compartment zips open from the outside; it's lined with cushy corderoy.

The Hacker has plenty of inside room, but isn't bulky when you're not toting a lot of extras.

This bag comes in 2 color schemes: navy/slate blue and black/black. It's yours for $120; not the cheapest around, but Timbuk2 bags, made from very tough ballistic nylon, will last you. I've been using one for 2 years and it barely looks used.