"Could" vs. "would." 3-legged underwear could allow you to go six days without changing. Nobody wants that, though. Wearable computing could give you a twitter feed in your field of vision. Nobody wants that, though. A HUD could give you a graphic equalizer of your Mudvayne MP3s as you sit in traffic. Nobody wants that, though. QED - HUDs are useful in places they've appeared. Fighters have had them for 40 years. Now jetliners do, too: http://www.owenzupp.com/Blog%20Images/HUD%202.JPG Importantly, however, the HUD on the 787 can be pushed out of the way when you don't want to use it, because it's kind of fucking annoying most of the time. Likewise, the examples of "wearable computing" I'm aware of where it demonstrates its utility are also in fighter jets: http://en.wikipedia.org/wiki/Helmet-mounted_display All of those can be turned off, though. Here's the bottom line - your information needs are very different when flying an F-35 in an air superiority dogfight than they are when walking to Starbuck's.