I love my Le Pliage bags for travel. The Le Pliage is actually a line of foldable bags made by the French company Longchamp Paris. My oldest one is still going strong after 10 years of fairly constant use.
The bags are very common in the duty free areas of most international airports. There are also a few companies in Canada that carry many of the styles and colors. The most common version is nylon, but I've also seen Pilage bags in leather and other fabrics in Europe. I sometimes think almost every woman in Paris has one tucked inside her handbag for shopping.
The tote style comes in about 15 different colors, different sizes XL-S, and different handle lengths. The line does include a backpack style as well as a crossbody style. Nordstorms carries a "made for Nordstrom" style that unzips at the bottom to create more volume. All Pilage bags fold up into a very small, compact package.
Lyn is right that the bags are not compartmentalized. Most just have a small inner pocket near the handle that fits my iPhone. I use small zippered nylon bags to compartmentalize my stuff so I actually prefer not having a bunch of inner pockets. When I travel, I carry a medium Pilage as a handbag with a large Pilage folded inside. Once I'm inside the airport, I switch things around by dropping my medium bag into the larger one which is roomy enough to accommodate the medium Pilage, my jacket, bottle of water, magazines, iPad, and all my other travel needs. The large bag fits very nicely under the seat or in an overhead compartment.
I love the versatility of the bags because I can always tuck one inside of a handbag to use as a shopping bag at my destination. I've also packed a weekend's worth of clothes into my larger Pilage bag to use as a carryon when we took a quick side-trip to Prague. And, because my bags are nylon, they are impervious to rain and easy to clean if they get dirty.
You can see all the styles and colours on the Longchamp website:
http://en.longchamp.com/pliage/nylon
I've purchased my bags in Paris, at Heathrow, and at Betty Hemmings in Toronto
http://www.bettyhemmings.com/tag/le-pliage/