Every week our team gets together on friday afternoons and have a presentation. The presenter rotates each week, and the topic can be programming language related, cool new libraries, theoretical -- or whatever related to our work.
I love doing Java Puzzlers since they do a great job of enriching your understanding of the language in a fun way. I've already done all of the Java Puzzlers that I could find from slides from Josh Bloche himeself. So this time I created my own, lifting the examples from the book.