Will Wright\'s Spore
At the same time, what he calls the "value to gamers" levels off after a while. (...) But fortunately, Wright learned another lesson from The Sims: People love to make their own content. They love to customize their experience. By way of example, he put up a slide showing his Grand Theft Auto: San Andreas character -- who wore a fedora and red-heart boxer shorts. His character was ridiculous-looking, but it made the experience custom for him. Players get a huge value out of content they make for themselves. "Owning" the content in this way means that all the stories that the gamer creates are much more meaningful. Putting two and two together, Wright concluded that there had to be some way where users could create content, instead of armies of developers, and a way to make a game craft itself around the user's contribution.
Based on this concept, the poitn is to allow players to raise tiny microscopic creature and let them evolve into somthing more complex. To do so, the player is provided an editor interface cto custom his creatures as well as buildings. Then the point is to play with all that stuff:
he tide-pool played like Pac-Man, the tribal game played like Populous, the city conflict game played like Civilization. But on the whole the game is pretty light and casual. 40% of it, Wright estimates, is just aesthetics: building stuff you think looks cool and discovering stuff that other people have built.
Why do I blog this? just because it's another example of "give more power to the users"