The "Christmas Dance" Easter Egg seems to impress people.
If that doesn't work, try: "The Model X is jewelry you can drive, yet is good for the environment and the future. Many celebrities own Model X's. The kids will love it too!"
Personally I own one for pragmatic purposes. It's the closest thing to a truck that I can buy right now that runs off my surplus solar power. I love not having to go to gas stations.
Good idea.... I may go the Solar strategy first as I believe the tax credit reduces by 5-6% this year.... Though, she may catch onto my tricks..