I really enjoyed the one entitled "Our place in the climate change", by someone named Aneria, PhD in Climatology. It was a really comprehensive talk, starting from what is a climate and why/how they exist, how to study them, their cycles, the recent events/anomalies and their causes, and what can we do to revert/lower the processus.
It was also a cool opportunity to discover le Loop, where I assisted to a private talk about shitty appliances, and gave one about pwning with radare2. I'm quite sure that I'll go there on a regular basis.
Old friend were met, new one were made, beers (at free price) were drank. Cool event.