Asus' entry for the Ultrabook market boasts longer battery life compared to most other competing models, thanks to Asu's energy-conserving Super Hybrid Engine technology. The 11.6-inch model also comes with instant-on technology that resumes the system in about two seconds, as well as a standby mode that will last up to 10 days. At 0.67 inches at its thickest point, the Zenbook UX21 is one of the thinnest models around. It also comes with Intel's Sandy Bridge Core processors (i3, i5 or i7), up to 4 GB of memory, and up to 256 GB of SSD storage. It also comes packed with plenty of I/O ports like USB 3.0 and micro-HDMI. The Zenbook also comes with Asus' SonicMaster technology for higher quality audio performance. The Zenbook UX21 is currently available for a starting price of $999.