If you're shaken, you are profoundly upset and disturbed. Witnessing a car nearly hit a bicyclist can leave you shaken — and just imagine how shaken the bicyclist is!
The shaken survivors of a house fire are left feeling so unnerved that they may actually be shaking a little bit. This adjective is perfect for describing someone who's been so upset by something that they almost feel like they've been physically shaken. And this literal sense of shaken can also be useful: "Don't open the shaken soda, it'll explode all over you!"