[Tomgs]

What I use it for the most especially early in the game is to move population around. You lose a lot of population on your homeworld because there is no more room to grow. If you take those excess population and put it on another world eventually when there are enough there they will get bonuses to production. Later on in the game most of my larger transports are moving mines and troops to the front lines but I almost always have some running population from world to world. Especially If I have conquored a world with a population that breathes another atmosphere.