I've been reading quite a bit lately about the Brushes iPhone app. Apparantly, George Columbo, one of the New Yorker cover artists often uses the app to make paintings of NYC on his iPhone, paintings of sufficiently high quality to grace the covers of that august publication. Check it out:
More amazing images can be found in the Brushes artists' gallery HERE, but some others I really liked are copied below. Guess I'll have to check it out - the idea of having such a highly-powered art app always in my pocket is, in a word, intoxicating.