Gotta love the open source empire building games, heres one for Pandora:

Freeciv is a Free and Open Source empire-building strategy game inspired by the history of human civilization. The game commences in prehistory and your mission is to lead your tribe from the stone age to the space age.
Latest beta release.
Removed SDL client, but will try to restore it again.
Updated libs and sources. See NEWS-2.6.