I was astounded to find the wikipedia article on freeskiing didn't have afterbang defined under the list of general Newschooler slang. I quickly added a definition but think this definition should be the product of a newschooler consensus considering the terms importance.
here's my first draft:
Similar to "stomping" a trick, this is when, after landing a trick, the skier non-chalantly absorbs the impact (legs loose but close together, arms relatively stiff, typically one hand in front and one in back though they are not restricted to these locations) while leaning back and proceeds to ski away in this reclined position. The emphasis is again appear to have exerted little effort at all regardless of the difficulty of the trick; the body language must appear natural and untensioned, lazy even.