This is a long read but very interesting. Most of the story is about reverse engineering the ability to emulate SNES hardware at a low level. Low level, in this case, means identical results come out of your software as would have come out of the actual chip. It is much harder than it sounds.
Even more interesting is the message that the intellectual property owners are very poor stewards of their own products. Video game software, for instance is generally released in a window of at most 10 years before it is replaced. US Copyright law allows for protection of up to 70 years beyond the author's death.
In that lengthly gap of time, the original medium of release becomes unusable if not properly stored or duplicated. I remember when I got my first CD-R drive. They said the discs would last ONE HUNDRED YEARS. I was lucky to have them last 10 if I tucked them away safely. Beyond the medium of storage, the devices themselves fail. Just look at the Xbox 360's RRoD phenomenon for a nice glimpse of the gloom that awaits kids who grow up fondly remembering that hardware platform.
Most surprisingly the best stewards of software are apparently the thieves of it. What an odd thing to consider.
