Beware: these puzzles are so hard, they may scorch your brain! Of course, some people like to get burned once in a while, especially by brilliantly executed crosswords with devilishly difficult clues. If you enjoy the Friday and Saturday offerings from sources like the New York Times, you'll love these tricky crosswords, which come with explanations for the toughest clues along with the answer grids. Solve with a pen at your own risk!