In Iraq, American troops have established their own Research & Development and procurement system. Its informal, and arises from curiosity, need and the ability to quickly share information via the Internet, and use the web to order interesting new stuff as well.
Two recent examples are battery powered LED headband flashlights and Silly String. LED (Light Emitting Diodes) have been around for decades, but in the past few years, LED lighting elements have become powerful enough to replace light bulbs in flashlights. The advantage of LEDs is that they draw less power, giving you 20-100 hours of use on two or three AA or AAA batteries (and depending on how many LEDs are used.) In Iraq, where new batteries are sometimes hard to get, the electrical power supply sometimes fails, and troops often have to operate under blackout conditions, LED lights solve many problems. Headband LED flashlights provide enough light to read by, but not so much that hostile gunmen will spot you. You can also get red LED elements, which is used for true blackout conditions. While the military has adopted some LED products, the troops have bought a lot more with their own money.
OK, LEDs make sense, but Silly String? This is a kids toy, a gun with a canister of plastic foam attached. Pull the trigger, and a string of plastic goes flying for about 12 feet. Harmless, kind of silly. But American marines found that Silly String was an excellent tool to search for trip wires when removing booby traps or roadside bombs. Officers were so impressed that they got the government to pay for the supplies of Silly String. The procurement people back in the United States were surprised at first, until the use of Silly String was explained.