To make it funky, each day the grid redraws itself with different coloured LEDs in each position.
Everything you need is in this Github repo. Clone it and then run advent.py
Because the images are just 8x8 bit, they can take a little bit of imagination to work out (the Dec 1st is a snowball fight, before you ask!). You can, of course use your own content for each day. The static pictures should go in the pngs folder: name them decx.png, where x is the day. Animations should be added as a list of frames to animations.py (follow the format of the existing ones).
You can use my 8x8grid drawing program to create your images and animations.
I wrote this in a bit of a rush so let me know if you spot any