This is probably relevant for lots of people here since ownCloud is one of the big open source projects in the movement for freedom from the web’s monopolies. Also I assume you like parties!
For those of you who are in Berlin these days, on Friday there’s a release party for ownCloud 5 at c-base:
https://daniel.molkentin.net/2013/03/11/owncloud-5-release-party-in-berlin/
I also heard there might be events in Utrecht and Nürnberg. And of course you’re welcome to spin up your own event!