I was in the market for a laptop messenger-style bag. I needed something that would hold my laptop, books, files, pens, calculator, etc. I looked at a few options, but decided on the Timbuk2 Commute (Large).

The bag is extremely well made. It is made primarily with HEAVY ballistic nylon. It is lined with pretty heavy nylon, and any fabric edges covered with piping. The clips for the shoulder strap are made of plastic, and to me, do not match the quality of the rest of the bag. They are however, heavy-duty and will likely last years of daily use.

The laptop side is adequate. The laptop pocket is Timbuk2's older corduroy lined version. It works well, and barring a huge impact, I think it will be more than able to protect my computer. There is also a thin, document-sized, pocket for magazines or other papers you might want separate from the messenger pocket. I want to make this known: my Dell 15.6" laptop FILLS the laptop pocket. I bought the large size. Keep that in mind if you do not own a MacBook.

The main pocket has two sections and contains LOTS or "organization" pockets. On the outside (immediately under the messenger flap) there are four non-zippered pockets for random stuff (I keep my earphones in one) and a zippered pocket with a key chain tether.

The front section is what I would call the "dump" pocket. It's not quite large or rigid enough for documents, but it is large enough to throw random things into. My checkbook, financial calculator, and laptop power cord usually end up in there. The divider between the front and back section also contains many organization pockets. There are three small, non-velcro pockets, 4 pencil slots, and one slightly larger velcro-covered pocket. The divider unzips to reveal a large extra pocket. I usually put medium sized items that don't fit in the small pockets but would be lost in the larger spaces in there (granola bars, eye drops, etc.)

The back section in the main pocket is the largest area. This is where all my files, folders, and books end up. There is also a velcro "reducer" at the top of the section. By default it is attached, but when you pull it apart it expands the pocket by a good 1"-1.5". I haven't done it yet, but I'm positive that I could use this bag as an overnighter bag and bring my laptop with me.

For airport x-ray the laptop side unzips and folds out. Instead of pulling your laptop out of the bag and putting it in a tote you leave it in the pocket. I would not walk any distance with the laptop side unzipped, but it makes getting through the security checkpoint that much easier.

Pros:
Well constructed
Ample organization
All black is appropriate for business casual
Way cheaper than TUMI (which I considered)

Cons:
Ballistic nylon is not quite as business appropriate as leather
Cheap looking shoulder strap clips
Not cheap ($100+)

Alternatives:
Solo Leather Portfolio Classic
TUMI T-Tech Laptop Messenger

Verdict: Big time BUY! Timbuk2 offers a limited lifetime warranty on materials and workmanship. The materials are all top notch. Even if I don't like the way the shoulder strap clips look, they are robust and solid. Make sure you buy a size that works for your laptop. Timbuk2 has a nice size chart on their website. The extra-padded shoulder strap would also probably be a nice addition to this bag. I have not bought it yet, but I plan to.