Valence Screenwriters Festival
I registered after the deadline, so I couldn't schedule my meetings as well as I would have liked. Despite that, I caught up with friends, met some very nice people, went to some truly enlightening talks, and had a few drinks – it had been a while.

This festival is very well organized for meeting people – with meetings set up in advance and an app to get in touch. And Valence, I forget every time, but it's really pretty.