This is one of the most fun and least practical ideas I've seen in quite a while. At first blush, the idea of using kite-based wind power to drive you car across country seems like a great idea. After all, the wind produces clean free energy, and if the kite skiers that we see in the bay are any indication, you can build up some significant speed using these fancy kites.
Once I watched the video below and started to think about what it would be like to actually use it, however, I saw a few problems. First of all. you need a straight stretch of road. If it turns the wrong direction you cold easily lose your source of power. Additionally, since since you are connected to the kite via long strings, any telephone poles, power lines or overpasses could require an immediate cessation of your trip. Even billboards near the road could be an issue. Add to that the low angle of the strings, and you can see that if you are on the wrong side of the road when a truck goes by, you could easily get your lines tangled with a fast moving semi truck going in the opposite direction and it's likely the result would be less than ideal.
In fact, maybe that is a better idea! Maybe you would have more luck just harpooning passing trucks and then skiing behind then until you reach your exit. Still I salute these pioneers of green energy transportation. I salute them for having a wacky idea, for actually getting out there and trying it (we all need to be reminded of the power of acting on your ideas), and for actually covering 5000km across the Australian desert using only $15 worth of electricity while having what looks like loads of fun. Well done!
The project actually was focused on building an electric vehicle that could be recharged via a wind turbine that it carried. It was sponsored by a company called Evonik. The video below has a more balanced portrayal of the overall project and you can also read a bit more here.