If I could create any technology in the world, it would be a device to record my thoughts when my hands are busy, like when I'm driving or jogging. One of the ironies of writing is that everything sounds great when its in your head; another is that cool ideas will always pop into your head when you can't stop to write them down. If I'm driving along, the perfect opening line for my article will zip past the inside of my eyeballs, and unless I repeat it over and over like some pleading mantra until I can get to a stoplight and pull out a pen and the back of the phone bill. When I do this, the pen will, by order of Murphy's Law, refuse to work, and I end up chiseling the faint outline in the paper, hoping it will be enough to remind me later.
But if I could invent the Insta-Brain 2000, I could just push the tiny 'record' button hidden behind my ear, catch all those thoughts, and transcribe them later, or even better, hook it up to a USB cable and let the computer transcribe it (a feature for the Insta-Brain 3000, perhaps). There could be drawbacks, of course, like forgetting to turn it off and it records the inner dialog while watching George Clooney, but any great invention will have a few bugs to work through. Just have to encrypt the transcript file, that's all.