Saw these on this food blog awhile ago, but I believe it is adapted from Martha Stewart (as many good things are). Matt and I are pretty obsessed with these now, having made them about three or four times on the grill in in the last month.
If you like salt and vinegar potato chips, I would STRONGLY recommend trying these out. The first time we did it we used white wine vinegar, since we were kind of scared of using just plain white vinegar (since it kind of seems like a cleaning product sometimes instead of a food product).
Now we just use white vinegar, since it is cheaper, and it is still delicious. The outsides get so crispy on the grill and the insides are tangy and delicious. SO into them.