When in Samus' ship, go to the radio And press the following symbols. Going from left to right, press the second symbol, the seventh symbol, the fifth symbol and then the first symbol. You'll be greeted by Iwata himself. Of course, this is in Japanese.

A brief translation...

Hello, this is Iwata from Nintendo. A president has to take things really seriously, even if it doesn't seem like it. It's understandable if you lose weight from stress...but I get fatter instead. Nobody thinks I'm taking it seriously.