There's a great little write-up of Billy Twitters and His Blue Whale Problem in this Sunday's New York Times. You can read it here, but the print edition comes with a piece of Adam Rex art, perfect for clipping, plus a crossword puzzle.
Also, a reminder for those in the Bay Area: Mac will be reading and signing Billy Twitters on Sunday, August 16, at a Great Good Place for Books in Oakland at 11:00 AM. Pick up a Times, come on over, and maybe Mac can give you an answer or two for the crossword.