Leave it to iconic game designer and Maxis cofounder Will Wright to one-up his own work on The Sims. While his dollhouse/life-drama simulator became phenomenally successful, he didn't just sit back and collect simoleans. After making a game about human lives, he started working on (and has finally released) Spore, which Wright himself nicknamed "SimEverything," since its focus extends beyond humanity and tackles life on a...well, galactic scale.
If you really need a quick one-line summary of what Spore is, 1UP would describe it as "intelligent design via minigames." The Spore "plot" (it's got one, honest) is about your species' multistage journey from panspermia all the way to the center of the galaxy. You start your run of minigames with the Cell stage (where you're just a single-celled organism munching at whatever you can get) and work your way through the Creature, Tribal, Civilization, and Space stages.