When you spring for a Chromebook, the choice between performance and ruggedness is usually an either/or proposition: you can get a durable machine or speedy hardware, but seldom both. Acer thinks it can strike a balance between the two. It's launching the Chromebook 11 C771, which theoretically blends a tough body with better-than-usual processing power. The system is the first 11.6-inch Chromebook to pack Intel's 6th-generation chips, which promise both a speed bump over rivals and very healthy battery life (up to 13 hours on a non-touch model). It starts off with a 1.6GHz Celeron chip, but you'll get Core i3 and i5 models in September that should be up to more demanding web tasks.