Seems like they've got some sort of EyeToy-style device in the works, at least
Are Nintendo working on an EyeToy-style camera for Gamecube? That's the question that's sweeping the net today after it was revealed that the company has trademarked names and logos - which you can see to the right - relating to the phrases 'Manebito/Camera' and 'Ningen copy/Manebito'. 'Ningen copy' translates from Japanese as 'person copy' while 'manebito' means 'someone who imitates'.
As for the two logos, they do hint that, if Nintendo are indeed working on a Gamecube camera, that you'll be able to use it to transpose your own face on to those of in-game characters. Also, if you look closely at the second logo (click on it to see a larger version), next to a little videocamera icon is what appears to be a Cube icon inside the second kanji character. Intriguing.
News source: gamesradar.com