Civilization: Beyond Earth arrived on PC last week and people at Gamereactor have been mostly very pleased with with the game. Still, if you are not yet sure if the brand new strategy game is for you, you can easily try it out first.
2K Games and Firaxis have released a demo of the game that lets you play the 100 first turns for free. You can download it from Steam. It is 5GB in size.
It's a cunning way to release a demo with a turn limit as many will find the lure to upgrade to the full game very difficult...