Astronomers are a skilled and resourceful bunch who like solving problems, creating interesting data visualisations, and developing new methods to do interesting science. A hack day is an opportunity to get help with an idea you've had but lack key skills, explore new tools, collaborate with people who are outside your research field and let your creativity loose on projects suggested by the group. We will be asking you to add any project ideas to a wiki in advance of NAM and to pitch ideas on the day. The day will be quite informal, so feel at liberty to drop in and out if you can't commit to the whole day.