If you are bored, have a read of this - it's quite interesting:
I will summarize for those of us with less time on our hands. Basically the logo originated from a Norse Woodcut of the two tailed siren Melusine, a greek mythical creature. They would sing to the sailors, enticing them to the rocky coasts with their enchanting songs, then make love to them before devouring their flesh. Neat.
I am definitely going to need to invest in a ladder.