This year, the annual Chaos Communication Congress goes online. For those who don’t know what that is have a look here: CCC | Home
For the online happening, more details can be found here: Congress - CCC Event Blog
Date: 27. – 30. December 2020 in a hackerspace somewhere.
Or, if you want to make a contribution yourself: https://content.events.ccc.de/haveyoursay/
tl;dr: The Chaos Computer Club e. V. (CCC) is Europe’s largest association of hackers.