Aer Duffel Pack
This is the bag I don't go anywhere without. I got this bag as a gift from my best friend Hoon, and I absolutely love it. It has great capacity to carry a week's worth of clothes, one or both of my laptops, a pair of shoes, along with my other essentials. There's pockets and sleeves for just about everything, including multiple laptop sleeves, a built-in ventilated shoe compartment, and more than four side pockets to store your documentation, cables, and other trinkets.
Even a year after carrying this bag around, I'm still discovering new ways to use this pack to store my travel gear. Also, it's undeniably stylish and very comfortable to wear, even with a heavy load. I don't think I'll be finding a better alternative for a long time.