15. Samsung Series 9 (2012)
The MacBook Air’s biggest threat carries the lightest weight of any ultrabook in its class, while sporting some impressive benchmarks and a gorgeous display. Even at 15 millimeters thick, Samsung’s second-gen laptop packs in a dominant 1.6 dual-core Core i7 processor, 128GB SSD, 8GB of RAM, and two USB 3.0 ports. Battery life holds up at an est. six hours and the new Silent Mode option leaves users operating in a noise-free environment.