The Kanken comes in several fun colors. But be sure not to leave it in direct sunlight, or it might fade.
Fjallraven backpacks are made with recycled materials and eco-friendly materials, so you can rest assured that you're doing your part for the environment. Moreover, they have a strong reputation for durability and dirt resistance.
You can even buy one online from places like REI. Some models have a handy boarding pass compartment, making them a good choice if you're traveling by plane.