Here comes gadget trouble: The SMS Guerrilla Projector is a one-off device made by Troika Art and Design in London. Operating under the bat-signal principle, the projector shoots a text message onto whatever surface you point it at, letting you paste your own personal messages on road signs, movie screens — even some innocent schlub's backside. Keep it clean, kids. The mischievous device also has a cell phone built into the handle, enabling you to dial in your clever slogans from afar. So you could theoretically leave it in your windowsill aimed at the building across the street, then wait for just the right moment for your noisy neighbor to pass by for you to text, "Eat it, Harvey!" Or just set it up in to point at a big blank wall, give out the number to a few thousand people, and see what happens. We're sure it'll be an experience that's "very special and disturbing," as the website suggests. As noted, the device is one of a kind, but you can contact Troika if you want to use it, or just throw together your own flashlight/cell phone/lens combo if you're feeling ambitious.