The big internet math off:
https://aperiodical.com/2018/06/announcing-the-big-internet-math-off/
And a sticker book, specifically mine:
http://mathoffstickerbook.com/friend/oFavGwW9Ar7JJfpM1jW2
For fun Matthew Scroggs @mrscroggs has put together a sticker book for this event, I’m unsure of what it is or what it does, it will be fun.