The "Mensa" series of language-based puzzles just keeps selling and selling - 240,000 copies so far - and here's the latest blockbuster entry, meant for a slightly younger age. It features 26 grids in the shape of each capital letter, plus 13 in the shape of lowercase letters and another 13 in the shape of commonly paired letters (such as ON, IT, and CH). To add to the appeal, all the grids come in interesting shapes, including easily recognizable animals and objects. And each puzzle contains a secret message too! An explanation page for each puzzle section explains just what to do.