People on Top Floors Age Faster.

Here's a handy tool that lets you calculate the relativistic effects of moving close to the speed of light.

For instance, if the ship you are on is accelerating at 1 g (equal to the force of gravity on Earth pushing on you the whole way) for 5 straight years (from the point of view of those on the ship), you would travel 83.52252766934345 Light Years distance, meanwhile 84.47909072415224 years would seem to pass for those on Earth and you would achieve a speed at the end of those 5 years that is 0.9999342611039113 the Speed of Light.

You can also set it so that you first accelerate and then decelerate at the half-way point of the journey. You don't get nearly as far, but at least you can stop when you get to where you're going.

Go ahead, start plugging in numbers. Have fun with it.