I'm on the phone so I won't google, but this is a very old story and if you go to the guy's website, he has a writeup of exactly how he did it. (and yes, the LEDs are hacked, they contain another hidden component)
So, indeed. Off on the details though, he's managed to sandwich the whole RF generator into that switch package. Mad props and soldering skills way beyond anything I could ever do.
https://plus.google.com/+HenrykGasperowicz/posts/dpwCPFDb3XM...
https://plus.google.com/+HenrykGasperowicz/posts/dpwCPFDb3XM...
https://plus.google.com/photos/+HenrykGasperowicz/albums/585...
So, indeed. Off on the details though, he's managed to sandwich the whole RF generator into that switch package. Mad props and soldering skills way beyond anything I could ever do.