Saga Bucado

What I would like to see is the ability to have a friend come into your game, create a character and hang out with you in the game world. They could come in on the same console or over the network. Their character would be saved with your saved games. They could come in when they liked or you could play on without them when they are not around. You don't need to set up servers and host the game for everyone. Just let people host their friends in their own game. This is something I used to do in Minecraft. It is a simple concept. I don't believe it would take a lot of resources to create, and it would greatly enhance the player experience.