Nintendo is coming out with a 3D version of its DS portable game system but its already issuing a warning on it. Nintendo says kids under six years old should not play with the system when it's in the 3D mode, which can be turned on or off (although why would you buy a 3DS and then turn the 3D off). The 3DS does not require special glasses but does require you to look at it in the right way with your head held just so. Doesn't seem like it can do any lasting damage but that it can make kids sick. The device is being trotted out at trade shows next month but even in the demo phase, young kids won't be allowed to play it in 3D.