I realized partway through the day yesterday that my right binding was really loose. And of course, this was the day that I didn't bother putting my screwdriver in my pocket.
I rode down the mountain as slowly and conservatively as I could and fixed it. Interestingly, because the NXT-AT bindings have that screw-on cover that goes over the binding plate, the bolts can't come all the way out. About halfway out, they "top out" onto the cover. That probably saved me.