The Camp take place on a former soviet military base and attracts technologists, hackers and engineers from around the world. It has a very strong hippie culture, but there is a mix of everyone and the atmosphere is great really.
Most talks are engineering, art or sociology related with a emphasis on security and privacy in the 21st century. I learned a ton, it was a very intellectually gratifying experience.
At night the camp becomes a very special place: https://upload.wikimedia.org/wikipedia/commons/b/bc/CCCamp11...
with some crazy and magical light and music shows.
A truly amazing event.
Compared to say FOSSDEM, the topics are more political and there are also talks about art and culture. But the best part of it is not the talks, but the super friendly, crazy, diverse people who organise all sorts of crazy things all over the place.
Where at FOSSDEM you'd find people wearing Tux shirts talking about code and drinking beer, at CCC you'll find people with bright blue hair making mate slush and Arduino knitting robots.
Almost all the talks are in English and it's very international, but there are some things that completely pass you by as a foreigner. It was only because my German friends told me that I attended some impromptu sexism discussion because something happened somewhere, and everyone speaking German was really upset.
And drinking Club Mate :-)
Some more info: