By far the biggest hit at our family this weekend was the Nintendo Wii. The kids are playing with it constantly...alone, against each other, against parents, you name it.
Christmas Day people were racing into the family room to see Grandpa take on someone in bowling or golf.
If you haven't tried on yet - do it. It's the next generation of UI. I downloaded the trial of Opera, and with some tweaks it will be a reasonable browser environment. If you could add in some voice recognition (wiimote as a microphone) it could be revolutionary.