they're called motorkhanas over here. I've done a couple of them a few years ago, and yes it can be very difficult remembering the more intricate courses - especially after a few helis around some of the markers... Plenty of people stuff it up.
Its definitely a specialised skill getting around these tight courses quickly, and next to impossible to beat the regulars. They are a good way to teach car control, and great fun.
Anyone thinking about going drifting should have a go at a motorkhanas first I reckon. Teaches precise control of slides that will translate well to drifting. And you will definitely learn something just by watching the good drivers.
Its also the cheapest form of motorsport going around - about $20 to enter a round of the QLD motorkhana series. There's even an Australian Championship! And you can do it in anything from mum's corolla to one of those mini specials like this:
