So culled from the recent ish of GamePro- how about that, getting something interesting and informative out of that particular mag?

Patent # 6,672,963 at uspto.gov, just pull it up through a search as the url is way too long to really bother with.

Plucked from said site:

A software emulator for emulating a handheld video game platform such as GAME BOY.RTM., GAME BOY COLOR.RTM. and/or GAME BOY ADVANCE.RTM. on a low-capability target platform (e.g., a seat-back display for airline or train use, a personal digital assistant, a cell phone) uses a number of features and optimizations to provide high quality graphics and sound that nearly duplicates the game playing experience on the native platform. Some exemplary features include use of bit BLITing, graphics character reformatting, modeling of a native platform liquid crystal display controller using a sequential state machine, and selective skipping of frame display updates if the game play falls behind what would occur on the native platform.
Nintendo's already filed a cease and desist order with Tapwave Zodiac developer Crimson Fire.

It poses the question of whether Nintendo inherently has the right to do this. While I suppose they technically do, on the surface it's just a sneaky means of targeting the true piracy that is ROM distribution. I see it further as just another way for Nintendo to stomp all over hobbyists and developers who want an alternative than shelling out for their licensed dev platforms. One wonders how rabid Nintendo will be over trying to purge the net of emulators that run on regular home PCs though.