It's recently been revealed that Miyamoto didn't in fact code Donkey Kong:

http://games.yahoo.com/blogs/plugged-in/funny-occasionally-dirty-hidden-messages-favorite-games-192013980.html

When Nintendo first got into creating arcade video games, it didn't yet have the capability to program them itself. This hidden message in the code of Donkey Kong shows that development of Nintendo's breakout hit was at least partially outsourced to a company called Ikegami Tsushinki:

CONGRATULATION !IF YOU ANALYSE DIFFICULT THIS PROGRAM,WE WOULD TEACH YOU.*****TEL.TOKYO-JAPAN 044(244)2151 EXTENTION 304 SYSTEM DESIGN IKEGAMI CO. LIM.

The message, among several other bits of code, helps prove Ikegami’s otherwise-hidden role in the game's development. Ikegami would later sue Nintendo for illegally producing extra Donkey Kong games without its consent, as it was also the contracted manufacturer, as well as reverse-engineering Ikegami's code to create Donkey

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