Molon Labe is Greek for "come and take them" (roughly). The expression comes from the ancient battle of Thermopylae when the Persian army vastly outnumbered a small contingent of (mostly) Spartans. The Persians didn't want to be bothered with a pointless little fight and cried out "Greeks! Give up your weapons!" and the Spartan King shouted back "Come and take them!"
The film "300" is quite good and speaks to the issue of the value of fighting for freedom very eloquently.