Lenovo on Monday unveiled the ThinkPad X1 Carbon, a lighter, quicker ThinkPad notebook computer that has features inspired by tablets and smartphones. Set to go on sale later this month, the ThinkPad X1 has 3G wireless connectivity, a 14-inch (35.5 centimeter) screen, it weigs just three pounds (1.3 kilograms), it has up to eight hours of battery life and the startup time was reduced by as much as half to under 20 seconds.