When using the nunchuck one can hit the x and y buttons at the bottom of the remote while holding the analog stick prong and without interfering with the motion control of the remote; it is an intuitive way to keep those buttons from going to waste if the developer really needs some buttons but wants to use the nunchuck piece.
Multiple people may control the same character. Maybe one person controls the legs with a remote and someone else controls the arms. Think of a mechanized robot with multiple limbs or guns that require multiple people to drive at once. So as a team you play as the same character essentially in online deathmatch against other teams in their robots. A more simple example might be the Millenium Falcon; while someone drives two people arm the cannons. The point is to spread the action out since each console can only handle four remotes (is that right?).
In a shooter if one aims with tilting up and down and turning left and right, then rolling the remote could make the character roll, zooming would work naturally along the z axis (perhaps with the push of a button), moving the remote along the x axis could perhaps allow peaking around corners; moving the remote along the y axis could allow for quick ducks or jumping. With most weapons, even a blunt object like a pistol could be swung freely for melee attacks (perhaps also with the toggle of a button).
What I am unsure of right now is if one is flying is the remote going to control like a flight stick responding to tilting and turning, and then feature deeper control when using the tilting in combination with 3D movements along the x, y, and z axises.
The remote could be used as a summoning tool; one could paint the creatures (with considerable control using the remote's 3D capabilities) selecting from color palets that are elemental thus generating by balance of colors the effectiveness of your creation (which should also be altered by paint stroke, shape, and graphic quality in black and white). This would have to be in cel shading. Not everyone would have the most detailed creatures, but that wouldn't be required (though very possible); the player would be taught first about shape, proportion, and complementary colors. You will be able to collect different elements, colors, clays, pigments; whatever else can depthen your palete and strengthen your creatures. So in the beginning you will start out just grasping turning a few lines into a 3D creature; as you get better you will be able to detail everything about the characters.
I would like a game with 3D Japanese puzzle boxes. That is the smallest game I will propose. I think it could be fun; especially if they could get the computer to randomly generate quality boxes so the game never ends. It just gets bigger and bigger and harder and harder. A true 3D successor to Tetris. It can only work with dual remotes.