I'm living in rural Japan now. I think a lot of the culture shock here has more to do with the ways that Japan seems so close to American culture, yet so far. So, it's a modern country with electric lights - but the light switches are a different style than US ones.
Finding that everywhere you go in the United States the light switches are all installed upside down. You walk in, reach to the side in the dark (at least the switch is still in the right place) and brush it downwards at it to turn it on - only to find that it isalready in the "on" position. It's more distracting than finding that people drive on the other side of the road.
To the weak, culture shock can ruin or even end a holiday or world travel backpacking trip. But to the strong and worthy, culture shock can be an enlightening experiencing. If you plan on traveling overseas to exotic places, culture shock is inevitable. What it comes down to is how you handle it. Its like a crash course lesson in an entire culture, which actually sounds pretty cool. So if you think you got it, add "experiencing culture shock" on your bucket list.