As far as patents go, Nintendo could very well be working on a portable device with some Wii capabilities. Filed in March, the patent discusses "a housing to be held by a player. The housing incorporates an XY-axis acceleration sensor to detect an acceleration in an X-axis and Y-axis direction and a Z-axis contact switch to detect an acceleration in a Z-axis direction." While it could not be plans for a portable Wii, it could very well be plans for an accessory to the console.
