"Very fast" here does not mean something like 100 miles per hour, or even as fast an a 747 airplane, or the Space Shuttle. Very fast here means, close to the speed of light, which is 186,000 miles per second, or 300,000,000 meters/second, or about 1 foot every nanosecond. This page will try to show you what a house might look like if you flew by is at one of these "near speed of light" speeds.
First off though, how is it that you can see a house? Take a look at the picture below:
You can't see anything if there's no light, so here, the Sun is illuminating the house. Notice that some of the Sun's light rays bounce off of the house and into your eyes. It is through these rays that you are able to see the house.
Now, light rays travel at the speed of light (obviously). What would happen if you were moving to the right at very near the speed of light? It seems like you'd sort of be racing with the light rays bouncing off of the house. They'd have a hard time catching you to get into your eyes! Also, rays that have to travel greater distances (like the one that bounces off of the bottom of the house) wouldn't even catch you until a bit later than the rest!
All of this provides for some interesting views of the world while moving "very fast."