Little known is the fact that Nintendo have long planned a degree of independence from their own consoles; the popularity of their titles have created a demand for Nintendo classics outside of the shrine we call the couch. Anyone that has flown a little would have played Super Mario on a long haul flight (the author reccomends Singapore Airlines, "The Friendly Skies"), and several big brand mobile companies now offer several Nintendo games on their phones. What provides this post-platform game experience? Emulation, software that mimics the native platform on alternative hardware.
US Patent #6,672,963 was filed in January this year and disallows any unlicensed implementation of emulation for the Game Boy Advance series on other platforms (including your homePC). While it's economically understandable that Nintendo may want to protect their assets, this patent threatens the development of interoperable gaming systems and the right to reverse engineer a product you have paid for even if just to find out how it works. The grass roots of game development was built on people learning from, and sharing, each others code, and it's patents like this that stifle small scale development efforts while keeping the money makers ahead of the game. Secondly Nintendo's patent is based on an assumption that emulation itself is, or can even be, illegal. Both Crimson Fire Entertainment and Gambit Studios are under fire right now and their protectors, the Electronic Frontier Foundation are on the case..