Super geeky, but I loooove The Visual Display of Quantitative Information by Edward Tufte.
I know, I know - the title sounds like the most boring subject imaginable. But it’s actually an amazing book. Beautifully illustrated and filled with incredible examples of how you can show complicated information simply, visually and accurately.
It’s incredible relevant for anyone involved with speakers, content and presentations at events. So often I see terrible presentations with hard to understand visuals. Books like this are great to understand how to show information to an audience - in a way that a) they’ll understand easily and b) they will take away the message you want.
Plus as a bonus you look super smart when you’re reading it on the train.