[Wade]

Hey! That would be a great peice of late technology! The ability to move planets and travel like a ship. Once the planet has attained self sustaining heat from the civilization. This was in the Ringworld series by Larry Niven. The Puppeteer race have their "Fleet of Worlds" of 5 planets. Home world and 4 farm planets.

Ringworlds and Sphereworlds could be made to travel also!
The Ringworld in the story was also adjusted to travel in the fourth novel, 'Ringworld's Children'.