Gesture-activated devices
From computers to phones, gesture activated devices are starting to become more common. It was really fun seeing them in movies, like in Minority Report, but now those ideas seem even better and more useful when we have them at our disposal daily.
Actually, one of the X-prize challenges:
https://en.wikipedia.org/wiki/Tricorder_X_Prize
#9 thats not the only thing about that movie that already exists
stun gun