Shigeru Miyamoto's talked in the past about working on smaller projects, but the only project of his we saw at E3 2012 was Pikmin 3. He's assured Joystiq he is still working on something but we probably won't see it until next year.
People like to ask me if I want to do a small project with a small team. I do like working with a small team, and I'm working with a number of small teams on a lot of different ideas, but the problem is because of all these different roles that I have to fulfill, it takes me a long time to write the design document. Maybe this time next year I'll have something ready to show you that perhaps will illustrate that idea.