Bring nothing! Unless u want to spend the night there. Bring ur backpack with sleeping bag. Its all wireless in every corners. So u can enjoy internet there for free.
And of course, there will be games, such as the all famous "werewolves". Techno insiders. People from Vietnam expert in Web 2.0 (if I'm not mistaken), from Thailand and singapore. it will be fun!
Have u visit the web? the details are there!
http://barcamp.org/BarCampJBSee u there!