I was doing a 6 months voluntary year in Latvia in a totally foreign environment for me without any knowledge of the language and soon after that an almost 3 months voluntary period in Russia, again my language knowledge was limited.

Languages! And pretty much anything that seems interesting, such as skydiving, bungeejumping, laser tag :) In general, I like to learn about new things, explore new places and try out different things, e.g. riding on cows, going out in weird costumes on the streets ... as long as it seems fun.