Gamespy have a preview up about Will "Sim" Wright's new game "Spore" basically the idea is your take a simple single celled organism and evolve it up into your own species of creatures, eventually creating your own civilisation and then exploring the galaxy. According to the article the creatures, buildings, vehicles are even planets are designed by the player, there's no developer created 3D models, it's all created procedurally by the player. The player eventually comes across other races and civilisations.. all created by other players.

It all sounds very open ended and a very "sand box" style of gameplay, which sounds awesome to me. But don't believe me, read it for yourself and check out some of the shots.