In this episode...   * How do you reuse an old radiotherapy mask?   * What is the optimal way to utilise postcodes in Scrabble?   * And, the results of our 2021 listener survey are in.    For more on radiotherapy masks, head on over to Macmillan. And do check out the Bravery Unmasked project for some truly incredible mask transformations.   If you want want even more from A Problem Squared, find us on Twitter and Instagram.   And as always, if you've got a problem or a solution, hit us up on our website www.aproblemsquared.com.