Skylanders: Spyro's Adventure figures at a pre-E3 event earlier this year, it seemed only a matter of time before some enterprising enthusiast cracked open both the toy figures and the "portal" base unit, and figured out how they wirelessly connected. Sure enough, a tinkerer named Brandon Wilson recently did just that, and posted his results on his personal website. In return, he got an official cease-and-desist letter from Activision a few days later, telling him to take the findings down immediately.
Wilson wrote a response to point out that most of Activision's accusations against him are inaccurate: He was not intending to share his findings with others (only saved them in a .zip file for his own personal use), and has no intention to circumvent the game at all, either by using the Skylanders hardware with an iOS device (since the technology is based on RFID), or by "tricking" the portal into thinking he owns a Skylanders figure when he doesn't.
Despite all of that, however, Wilson has agreed to follow the cease-and-desist order. It seems a shame -- some of the most fun hacks have come out of toys both old and new, and if Wilson wants to dissect toys he's purchased for his own enjoyment, that seems reasonable. We've contacted Activision to try and get an official position; it's likely we haven't heard the last of this just yet.