Check this out:

From: http://damianbreach.com/2009/?p=498

Someone should make some fibreglass berms and humps and stuff that you can lay out in a parking lot and bolt together. Like some kind of pump track equivalent of Scalextric.

Even on dirt areas you could lay that stuff down and sprinkle with dirt to stop having to re-form the track all the time!

Anyone here have the necessary skilz for that?