The cool voice assistant that runs on the iPhone 4S? Years ago, someone thought what Apple calls Siri would be a valuable tool for the military. Come to think of it, most of the technology we use — whether to cook our food, figure out directions, or gawk at adorable pictures of animals — was in some way designed to help, however tangentially, America go to war. Armchair sociologists like to ponder the distance between military and civilian life. In the tech world, at least, they're not so far apart. Innovations that began with the U.S.' well-funded defense establishment almost always filter down into commercial, mundane usage. Sometimes in unexpected ways. Here are some of our favorite examples. Siri, can you think of some more? Darpa Funds the Mouse, Hypertext, Even Computer Windows Just think: If Doug Engelbart hadn't had a trippy vision while driving to his job at NASA, we might be living in a very different world. Engelbart had a waking dream of passageways to a networked world, powered by cathode ray tubes, where communications and organization became far more efficient than in augmentation-free reality. Skip ahead a few years, and Engelbart's Augmentation Research Center played around with all kinds of weird interfaces for human-machine collaboration. One of them was a weird wooden box that helped you select different bits of text on a screen, the better to enter a command. Voila: the first mouse. That wasn't the end. Engelbart came up with the hypertext language. His idea for organizing computer screens through virtual windows gave us an intuitive way to systemize all the information computers provide — and something to do after pointing a mouse at something. Where'd Engelbart get these ideas? His time in the Navy helped. While reading an article in the Atlantic by legendary scientist Vannevar Bush at a Red Cross library, Engelbart was turned on to the idea of an automated library system. That influenced his seminal 1962 article "Augmenting Human Intellect." The seed money for his projects came from the Air Force Office of Scientific Research. Later on, he'd get cash from an obscure military arm, the Advanced Research Projects Agency — later to become the blue-sky research organ known as Darpa. One of the places Engelbart spent ARPA's money: his lab at Stanford, which became the Stanford Research Institute — and later SRI International. In 2008, SRI spun off a commercial firm called Siri Inc., which Apple purchased a few years later. The fruits of that collaboration: the Siri voice-activated data assistant on the next-gen iPhone. Photo: Darpa

GPS There was a time, not all that long ago, when you actually had to be able to read a map to figure out where you were going. Now, a little gadget perched on your dashboard does the direction-finding for you. Thank a suite of six satellites, launched into the heavens in the 1950s by the Navy and Darpa to keep tabs on the Russkies. Designed to monitor "the Doppler shift in the frequency of Sputnik’s radio transmissions," the team quickly learned that they had a pretty reliable system for determining location — TRANSIT, the first satellite positioning system. Over the next two decades-plus, various iterations fine-tuned the capability, until a unified navigation system launched from Cape Canaveral in 1989. That was the NAVSTAR Global Positioning System — and the birth of GPS. Photo: Flickr/Kimmo Palosaari

Laptops Like your laptop? Thank the U.S. Army, which funded the development of ENIAC, the world's first general purpose electronic computer, during World War II to help calculate artillery trajectories. However, computers like ENIAC weren't the small user-friendly machines we're used to today. They were massive machines reliant on vacuum tubes, which had a tendency to fail and require replacement. Bell Labs invention of the transistor in 1947 made the much smaller, more reliable devices a better alternative to tubes. Still, their use was limited by the needlework of soldering individual transistors into place. In 1958, Texas Instruments' Jack Kilby, working on the U.S. Army Signal Corps-funded the Micro-Podule program, came up with the idea of building transistors onto a board with other components using a single material instead of soldering new ones in. Thus, the Integrated Circuit or "chip" was created. In the '70s, Darpa provided a testbed for different microchip designs. In the '80s, the agency funded the development of high-speed integrated circuits, which allowed our computers to shrink way, way down. Without the help, we might have still had netbooks and laptops... but only if we were Biggest Loser-sized** . Photo: U.S. Army

Microwave Oven The origins of the microwave are even freakier than this '60s-era mockup of a hanging heat lamp that fried your bacon. Percy Spencer, an engineer with the defense giant Raytheon, thought he was building magnetron for radar sets. Suddenly he discovered his pants were a sticky mess. A Mr. Goodbar he kept in his pocket had melted from the heat emitted from his active radar set. From that embarrassing accident came a multimillion dollar industry — and one of the great twin blessings and curses of the American kitchen. Photo: Flickr/SportSuburban

Cellphones Actress Hedy Lamarr was the first major starlet to go naked on the silver screen. Her second most important contribution? An idea she cooked up in 1941 with avant-garde composer George Antheil for a secret communications system. Instead of using a single frequency to transmit information wirelessly, their signals hopped between 88 different frequencies. It'd be all but impossible to snoop on, or jam. The U.S. Navy fiddled with the idea during World War II. Then it lay dormant for decades. But today, it's how cellphones manage to lock in, even when they're inside urban canyons or competing with the electromagnetic soup that is the modern city. (No AT&T jokes, please.) Around the same time, the Galvin Manufacturing company developed wireless communications products for the U.S. War Department. A backpack-based version of the system dubbed the "walkie talkie" used interference-resistant FM radio transmitters and receivers to create two way communications up to 20 miles. Its smaller handheld cousin, the "handie talkie," resembled a rudimentary early mobile phone. It operated on AM and had a maximum range of one mile over land. After the war, Galvin changed its name to Motorola Inc. In 1983, it would go on to manufacture the first cellular phone approved for use by the FCC. Photo: Flickr/KB35

T-Shirts Not all defense spinoffs are high tech, though. Consider the military's various fashion forward innovations. > Long a fashion fixture, the trench coat owes its name and origin to the gritty trench warfare of World War I. One of the early models was designed by Thomas Burberry (of the famously plaid-patterned Burberry company) and submitted to Britain's War Office in 1901. Its use of gabardine, a tough, water-resistant fabric that Burberry had invented in 1880, made it a handy piece of outwear in the often cold and wet battlefields at the time. Available only for use by officers, its iconic shoulder straps were originally used to display rank insignia. The humble T-shirt owes much of its popularity to the Navy, as well. Different models of T-shirt had existed for some time before World War II, but during the war, the Navy issued sailors with a T-type quarter sleeve knit undershirts. The shirt proved popular and was adopted among the other services. After the war, veterans took their T-shirts home with them and created a new demand for the garment in the civilian market.

Google Earth It probably should come as no surprise that the investment arm of the U.S. spy apparatus helped back a tool that eventually gave us a satellite's eye view of the entire world. In 2003, In-Q-Tel, which you can think of as the CIA's VC adjunct, announced it would fund a company specializing in "interactive 3D earth visualization." That was Keyhole. The very next year, Google bought the firm — and its relationship with In-Q-Tel. The search giant parlayed it all into its phenomenally successful Google Earth mapping platform. Which, it's worth noting, is hardly the last collaboration between Google and the CIA. Photo: Flickr/Born 1945