For Portuguese speakers you also have "saudade", which is also hard to express in other languages, as it means a mix of nostalgia, home sickness, to miss something, depending on the context.
Dinosaur Comics: http://www.qwantz.com/index.php?comic=2129
The alt-text for the comic is particularly fascinating as well. To know that Brazil celebrates a National Saudade Day is reassuring and romantic.