Wiiflap enthusiasts, let loose your most raucous rattles of delight: a new Wiister Egg of a flap has been spotted in a Spanish Wii forum. Says Joystiq:

A member of the Spanish gaming forum Canal Nintendo has posted an image that appears to feature another mystery port located near the bottom of the left side of Wii.

Speculation about the new port includes DS slot, SD memory slot, Fleshlight Rumblepak peripheral compatibility, and Juicy Fruit dispenser. Eliza gauger

Another Wii mystery port spotted [Joystiq]
Month-old forum post on the same topic [WarpPipe]