[nubs]

They can be pretty crazy to figure out how to navigate on larger intersections (which have the double diamond plus other intersections in the same area). I can't tell you how many times I've missed my turn and had to take a long way around trying to get through this intersection in Austin: http://www.openstreetmap.org/#map=17/30.23595/-97.82471

Edit: On second thought I'm not entirely sure that is a double-diamond, although I've heard people refer to it as one. It doesn't seem to match up with the wikipedia article, however.